Soil Basics, Management and Rhizosphere Engineering for Sustainable Agriculture 9781351044264, 1351044265

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Soil Basics, Management and Rhizosphere Engineering for Sustainable Agriculture
 9781351044264, 1351044265

Table of contents :
Content: Cover
Half Title
Title Page
Copyright Page
Contents
Preface
About the Authors
Section I: Soil Basics
Chapter 1: Introduction to Sustainable Agriculture
1.1 Introduction
1.1.1 History of Agriculture
1.1.2 Our Earth is Unique
1.1.3 Conventional versus Sustainable Agriculture Practices
1.1.3.1 Conventional Agriculture
1.1.3.2 Sustainable Agriculture
1.2 Sustainable Farming Methods and Practices
1.2.1 Permaculture
1.2.2 Biodynamics
1.2.3 Hydroponics and Aquaponics
1.2.4 Urban Agriculture
1.2.5 Agroforestry and Food Forests
1.2.6 Rotating Crops and Polycultures. 1.2.7 Growth of Heirloom and Older Varieties1.2.8 Natural Animal Rising
1.2.9 Natural Pest Management
1.2.10 Mulching, Groundcovers, and Manual Control
1.2.11 Reducing or Eliminating Tillage
1.2.12 Benefits of Sustainable Agriculture
1.2.13 Why Sustainable Agriculture is so Important?
1.2.14 Meeting the Global Challenge of Sustainable Food, Fuel and Fiber Production
1.3 Soil Basics
1.3.1 Soil is a Basic Building Block for Life on Earth
1.3.1.1 What is Soil?
1.3.1.2 Why Soil is so Important?
1.3.1.3 Soil Science and Education. 1.3.1.4 Some Facts and Figures of Soils in Sustainable Agriculture1.3.1.5 The General Features of Soils
1.3.1.6 General Uses of Soils
1.3.1.7 Approaches of Soil Study
1.3.2 Soil Formation and Classification
1.3.2.1 Soil Formation
1.3.2.2 Soil Classification
1.3.3 Soil Physical and Chemical Properties
1.3.4 Soil Water
1.4 Soil Management for Sustainable Agriculture
1.4.1 Soil Management Practices
1.4.2 Advantages of Soil Management
1.4.3 Healthy Soil for Sustainable Agriculture
1.4.4 Soil Erosion
1.4.5 Soil Pollution
1.4.6 Soil Testing for Better Nutrient Management. 1.4.7 Soil Preparation and Tillage1.4.8 Soil Organic Matter: Composting
1.4.9 Organic Farming: An Enterprise of Sustainable Agriculture
1.5 Plant Nutrient Management and Plant Protection
1.5.1 Soil Nutrient Management
1.5.1.1 Soil Nutrient Balance
1.5.1.2 Advantages Plant Nutrient Management
1.5.1.3 Sources of Plant Nutrients
1.5.2 Plant Mineral Nutrient
1.5.3 Chemical Fertilizers and Fertigation
1.5.4 Organic Fertilizers
1.5.5 Biofertilizers
1.5.6 Biopesticides and Bioherbicides
1.6 Soil Organisms in Sustainable Agriculture
1.6.1 Soil Microbiolgy. 1.7 Soil, Water, and Plant Relations1.7.1 Plant Forms and Functions
1.7.2 Plant Growth and Development
1.7.3 Water Absorption and Transportation in Plants
1.7.4 Mechanism of Mineral Nutrient Uptake in Plants
1.7.5 Abiotic Stress: Plant Response to Moisture and Salt Stress
1.8 Rhizosphere Engineering for Sustainable Agriculture
1.8.1 Rhizosphere Structure and Root Exudation
1.8.2 Rhizosphere Interactions
1.8.3 Rhizosphere Engineering
1.8.4 Bioremediation
Summary
Further Reading
Chapter 2: Soil Formation and Classification
2.1 Introduction
2.2 Pedogenesis.

Citation preview

Soil Basics, Management and Rhizosphere Engineering for Sustainable Agriculture Channarayappa and D P Biradar

Soil Basics, Management, and Rhizosphere Engineering for Sustainable Agriculture

Soil Basics, Management, and Rhizosphere Engineering for Sustainable Agriculture

Channarayappa D.P. Biradar

CRC Press Taylor & Francis Group 6000 Broken Sound Parkway NW, Suite 300 Boca Raton, FL 33487-2742 © 2019 by Taylor & Francis Group, LLC CRC Press is an imprint of Taylor & Francis Group, an Informa business No claim to original U.S. Government works Printed on acid-free paper International Standard Book Number-13: 978-1-138-48692-8 (Hardback) This book contains information obtained from authentic and highly regarded sources. Reasonable efforts have been made to publish reliable data and information, but the author and publisher cannot assume responsibility for the validity of all materials or the consequences of their use. The authors and publishers have attempted to trace the copyright holders of all material reproduced in this publication and apologize to copyright holders if permission to publish in this form has not been obtained. If any copyright material has not been acknowledged please write and let us know so we may rectify in any future reprint. Except as permitted under U.S. Copyright Law, no part of this book may be reprinted, reproduced, transmitted, or utilized in any form by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying, microfilming, and recording, or in any information storage or retrieval system, without written permission from the publishers. For permission to photocopy or use material electronically from this work, please access www.copyright.com (http://www.copyright.com/) or contact the Copyright Clearance Center, Inc. (CCC), 222 Rosewood Drive, Danvers, MA 01923, 978-750-8400. CCC is a not-for-profit organization that provides licenses and registration for a variety of users. For organizations that have been granted a photocopy license by the CCC, a separate system of payment has been arranged. Trademark Notice: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation without intent to infringe. Visit the Taylor & Francis Web site at http://www.taylorandfrancis.com and the CRC Press Web site at http://www.crcpress.com

Contents Preface.......................................................................................................................................................................................xlix About the Authors..........................................................................................................................................................................li

Section I  Soil Basics Chapter 1 Introduction to Sustainable Agriculture................................................................................................................... 3 1.1 Introduction................................................................................................................................................... 3 1.1.1 History of Agriculture................................................................................................................... 3 1.1.2 Our Earth is Unique....................................................................................................................... 3 1.1.3 Conventional versus Sustainable Agriculture Practices................................................................ 4 1.1.3.1 Conventional Agriculture............................................................................................. 4 1.1.3.2 Sustainable Agriculture............................................................................................... 5 1.2 Sustainable Farming Methods and Practices................................................................................................ 6 1.2.1 Permaculture.................................................................................................................................. 6 1.2.2 Biodynamics.................................................................................................................................. 6 1.2.3 Hydroponics and Aquaponics........................................................................................................ 6 1.2.4 Urban Agriculture.......................................................................................................................... 6 1.2.5 Agroforestry and Food Forests...................................................................................................... 7 1.2.6 Rotating Crops and Polycultures................................................................................................... 7 1.2.7 Growth of Heirloom and Older Varieties...................................................................................... 7 1.2.8 Natural Animal Rising.................................................................................................................. 8 1.2.9 Natural Pest Management.............................................................................................................. 8 1.2.10 Mulching, Groundcovers, and Manual Control............................................................................. 8 1.2.11 Reducing or Eliminating Tillage................................................................................................... 8 1.2.12 Benefits of Sustainable Agriculture............................................................................................... 8 1.2.13 Why Sustainable Agriculture is so Important?.............................................................................. 9 1.2.14 Meeting the Global Challenge of Sustainable Food, Fuel and Fiber Production.......................... 9 1.3 Soil Basics................................................................................................................................................... 10 1.3.1 Soil is a Basic Building Block for Life on Earth......................................................................... 10 1.3.1.1 What is Soil?.............................................................................................................. 10 1.3.1.2 Why Soil is so Important?......................................................................................... 10 1.3.1.3 Soil Science and Education........................................................................................ 10 1.3.1.4 Some Facts and Figures of Soils in Sustainable Agriculture..................................... 11 1.3.1.5 The General Features of Soils................................................................................... 12 1.3.1.6 General Uses of Soils................................................................................................. 12 1.3.1.7 Approaches of Soil Study.......................................................................................... 13 1.3.2 Soil Formation and Classification................................................................................................ 14 1.3.2.1 Soil Formation........................................................................................................... 14 1.3.2.2 Soil Classification...................................................................................................... 14 1.3.3 Soil Physical and Chemical Properties........................................................................................ 14 1.3.4 Soil Water..................................................................................................................................... 14 1.4 Soil Management for Sustainable Agriculture............................................................................................ 15 1.4.1 Soil Management Practices.......................................................................................................... 15 1.4.2 Advantages of Soil Management................................................................................................. 15 1.4.3 Healthy Soil for Sustainable Agriculture..................................................................................... 15 1.4.4 Soil Erosion.................................................................................................................................. 16 1.4.5 Soil Pollution................................................................................................................................ 16 1.4.6 Soil Testing for Better Nutrient Management.............................................................................. 16 1.4.7 Soil Preparation and Tillage........................................................................................................ 16 1.4.8 Soil Organic Matter: Composting................................................................................................ 17 1.4.9 Organic Farming: An Enterprise of Sustainable Agriculture...................................................... 17 v

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1.5

Plant Nutrient Management and Plant Protection....................................................................................... 17 1.5.1 Soil Nutrient Management........................................................................................................... 18 1.5.1.1 Soil Nutrient Balance................................................................................................. 18 1.5.1.2 Advantages Plant Nutrient Management................................................................... 18 1.5.1.3 Sources of Plant Nutrients......................................................................................... 18 1.5.2 Plant Mineral Nutrient................................................................................................................. 19 1.5.3 Chemical Fertilizers and Fertigation........................................................................................... 19 1.5.4 Organic Fertilizers....................................................................................................................... 19 1.5.5 Biofertilizers................................................................................................................................ 20 1.5.6 Biopesticides and Bioherbicides.................................................................................................. 20 1.6 Soil Organisms in Sustainable Agriculture................................................................................................. 20 1.6.1 Soil Microbiolgy.......................................................................................................................... 20 1.7 Soil, Water, and Plant Relations.................................................................................................................. 21 1.7.1 Plant Forms and Functions.......................................................................................................... 21 1.7.2 Plant Growth and Development................................................................................................... 21 1.7.3 Water Absorption and Transportation in Plants.......................................................................... 22 1.7.4 Mechanism of Mineral Nutrient Uptake in Plants....................................................................... 22 1.7.5 Abiotic Stress: Plant Response to Moisture and Salt Stress........................................................ 22 1.8 Rhizosphere Engineering for Sustainable Agriculture............................................................................... 23 1.8.1 Rhizosphere Structure and Root Exudation................................................................................ 23 1.8.2 Rhizosphere Interactions............................................................................................................. 23 1.8.3 Rhizosphere Engineering............................................................................................................ 23 1.8.4 Bioremediation............................................................................................................................. 24 Summary................................................................................................................................................................ 24 Further Reading...................................................................................................................................................... 25 Chapter 2 Soil Formation and Classification.......................................................................................................................... 27 2.1 Introduction................................................................................................................................................. 27 2.2 Pedogenesis.................................................................................................................................................. 27 2.2.1 Soil Forming Materials................................................................................................................ 27 2.2.1.1 Igneous Rocks............................................................................................................ 28 2.2.1.2 Sedimentary Rocks.................................................................................................... 29 2.2.1.3 Metamorphic Rocks................................................................................................... 29 2.2.2 The Process of Soil Formation.................................................................................................... 29 2.3 Formation of Soil: Weathering and Transportation.................................................................................... 29 2.3.1 Weathering................................................................................................................................... 30 2.3.2 Weathering of Rocks and Minerals............................................................................................. 30 2.3.3 The Basic Processes of Weathering............................................................................................. 30 2.3.4 Physical Weathering of Rocks..................................................................................................... 30 2.3.4.1 Physical Condition of Rocks...................................................................................... 31 2.3.4.2 Action of Temperature............................................................................................... 31 2.3.4.3 Mechanical Action of Water...................................................................................... 31 2.3.4.4 Action of Wind........................................................................................................... 32 2.3.4.5 Plants and Animals.................................................................................................... 32 2.3.4.6 Atmospheric Electrical Phenomenon........................................................................ 32 2.3.5 Chemical Weathering of Rocks................................................................................................... 32 2.3.5.1 Chemical Processes of Weathering........................................................................... 32 2.3.6 Biological Weathering of Rocks.................................................................................................. 33 2.3.6.1 Man and Animals...................................................................................................... 33 2.3.6.2 Higher Plants and Roots............................................................................................ 34 2.3.6.3 Microorganisms......................................................................................................... 34 2.3.7 The Components Released During the Weathering Process....................................................... 34 2.3.8 Weathering of Minerals............................................................................................................... 34 2.3.8.1 Climatic Conditions................................................................................................... 34 2.3.8.2 Physical Characteristics............................................................................................. 34 2.3.8.3 Chemical and Structural Characteristics................................................................... 34

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2.4

2.5

2.6

Soil Forming Processes............................................................................................................................... 34 2.4.1 Fundamental/Key Soil Forming Processes................................................................................. 35 2.4.2 Specific Soil Forming Processes................................................................................................. 35 2.4.2.1 Calcification............................................................................................................... 35 2.4.2.2 Decalcification........................................................................................................... 36 2.4.2.3 Podzolization............................................................................................................. 36 2.4.2.4 Laterization................................................................................................................ 36 2.4.2.5 Gleization................................................................................................................... 36 2.4.2.6 Salinization................................................................................................................ 37 2.4.2.7 Desalinization............................................................................................................ 37 2.4.2.8 Solonization or Alkalization...................................................................................... 37 2.4.2.9 Solodization or Dealkalization.................................................................................. 37 2.4.2.10 Pedoturbation............................................................................................................. 37 2.4.3 Hydromorphic Profile Development............................................................................................ 37 2.4.4 Soil Forming Factors................................................................................................................... 37 2.4.5 Formation of True Soil from Regolith......................................................................................... 37 2.4.6 Passive Soil Forming Factors....................................................................................................... 37 2.4.6.1 Parent Material.......................................................................................................... 37 2.4.6.2 Time........................................................................................................................... 39 2.4.6.3 Topography or Relief................................................................................................. 39 2.4.6.4 Landscape Position.................................................................................................... 39 2.4.6.5 Position....................................................................................................................... 40 2.4.6.6 Slopes......................................................................................................................... 40 2.4.6.7 Contour Lines............................................................................................................ 41 2.4.6.8 Maps........................................................................................................................... 42 2.4.7 Active Soil Forming Factors........................................................................................................ 43 2.4.7.1 Climate....................................................................................................................... 43 2.4.7.2 Biological Factors...................................................................................................... 44 2.4.8 Development of Soil Profile......................................................................................................... 44 2.4.8.1 Changes to the Soil Profile........................................................................................ 45 2.4.8.2 Components of the Soil Profile.................................................................................. 45 2.4.8.3 Master Horizons of Soil............................................................................................. 45 2.4.8.4 Horizon Numbering and Suffixes.............................................................................. 48 2.4.8.5 Transition Horizons................................................................................................... 49 2.4.8.6 Subordinate Distinctions............................................................................................ 49 2.4.8.7 Buried Soils................................................................................................................ 49 2.4.8.8 Soil Formation is Continuous Process....................................................................... 49 Soil Types and Soil Classification............................................................................................................... 50 2.5.1 Basic Characteristics of Soils...................................................................................................... 50 2.5.2 Soil as an Engineering Material.................................................................................................. 50 2.5.3 Size Range of Soil Grains............................................................................................................ 51 2.5.4 Shape Characteristics of Sand Grains......................................................................................... 51 2.5.4.1 Shape Characteristics of Clay Grains........................................................................ 52 2.5.4.2 Specific Surface......................................................................................................... 52 2.5.5 Soil Structure or Fabric................................................................................................................ 52 Soil Survey and Mapping............................................................................................................................ 52 2.6.1 What is a Soil Survey?................................................................................................................. 52 2.6.2 How Soil Surveys are Made?....................................................................................................... 53 2.6.3 Types of Surveys.......................................................................................................................... 53 2.6.4 Soil Survey Interpretation............................................................................................................ 53 2.6.4.1 Land Capability Classification................................................................................... 53 2.6.4.2 Arable Land............................................................................................................... 54 2.6.4.3 Nonarable Land.......................................................................................................... 54 2.6.5 Usefulness of Soil Survey Report to Various Stakeholders......................................................... 54 2.6.5.1 Agricultural Producers, Farm Managers, and Consultants....................................... 54 2.6.5.2 Bankers, Investors, Land Appraisers, Credit Agencies and Directors of Tax Equalization........................................................................................................ 54

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2.6.5.3 Natural Resource Education...................................................................................... 55 2.6.5.4 Windbreaks, Woodland, and Wildlife....................................................................... 55 2.6.5.5 Highway/Construction Engineers and Land Developers........................................... 55 2.6.5.6 Planning Boards, Health Officials, and Municipal Officials..................................... 55 2.6.5.7 Geographical Information Systems (GIS)................................................................. 55 2.6.5.8 Water Resource Vulnerability.................................................................................... 55 2.6.5.9 Soil Surveys can Help to Manage Resources for Sustained Productivity................. 55 2.6.6 Do Soil Maps have Limitations?.................................................................................................. 55 2.7 Soil Classification........................................................................................................................................ 56 2.7.1 Why Classify Soils?..................................................................................................................... 56 2.7.2 Soil Classification Systems.......................................................................................................... 56 2.7.2.1 American Association of State Highway and Transportation Officials (AASHTO)....... 56 2.7.2.2 Unified Soil Classification System (USCS)............................................................... 57 2.7.2.3 USDA Soil Classification System.............................................................................. 57 2.7.3 Hierarchy of Categories in Soil Taxonomy.................................................................................. 57 2.7.3.1 Orders......................................................................................................................... 57 2.7.3.2 Suborders................................................................................................................... 57 2.7.3.3 Great Groups.............................................................................................................. 57 2.7.3.4 Subgroups.................................................................................................................. 57 2.7.3.5 Families...................................................................................................................... 58 2.7.3.6 Series.......................................................................................................................... 58 2.7.4 Different Soil Orders................................................................................................................... 58 2.7.5 Diagnostic Horizons.................................................................................................................... 59 2.7.6 Importance of Soil Classification................................................................................................ 59 2.7.7 Approaches of Soil Classification................................................................................................ 60 2.7.7.1 Engineering................................................................................................................ 60 2.7.7.2 Soil Resources............................................................................................................ 60 2.7.8 Soil Types and Testing................................................................................................................. 60 2.7.8.1 Color........................................................................................................................... 60 2.7.8.2 Compaction................................................................................................................ 60 2.7.8.3 Moisture Content....................................................................................................... 61 2.7.8.4 Organic Content......................................................................................................... 61 2.7.8.5 Soil pH....................................................................................................................... 61 2.7.8.6 Soil Profile................................................................................................................. 61 2.7.8.7 Soil Structure and Texture......................................................................................... 62 2.7.9 Characteristics of Different Soil Types........................................................................................ 62 2.7.9.1 Rope Test.................................................................................................................... 62 2.7.9.2 Jar Test....................................................................................................................... 62 2.7.9.3 Soil Types Based on Vernacular System................................................................... 62 2.7.10 Visual (Field) Classification of Soil Sample................................................................................ 62 2.7.10.1 Coarse Grained.......................................................................................................... 64 2.7.10.2 Fine-Grained Soils..................................................................................................... 64 2.7.11 British Soil Classification System................................................................................................ 64 2.7.11.1 Organic Soils.............................................................................................................. 64 2.7.11.2 Soil Types Based on Scientific System...................................................................... 64 2.7.11.3 Soil Types Based on the Soil Horizons...................................................................... 65 2.7.11.4 Soil Types Based on the Particle Size........................................................................ 65 2.7.11.5 Soil Types Based on the pH....................................................................................... 66 Summary................................................................................................................................................................ 66 Further Reading...................................................................................................................................................... 67 Chapter 3 Physical Properties of Soil..................................................................................................................................... 69 3.1 Introduction................................................................................................................................................. 69 3.2 Composition of Soils................................................................................................................................... 69 3.2.1 Organic Materials in Soil............................................................................................................. 69

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3.2.2 3.2.3

Inorganic Materials in Soil.......................................................................................................... 70 Air in Soil.................................................................................................................................... 70 3.2.3.1 Factors Affecting the Composition of Soil Air.......................................................... 71 3.2.3.2 Exchange of Gases between Soil and Atmosphere.................................................... 71 3.2.3.3 Importance of Soil Aeration...................................................................................... 71 3.2.4 Water in Soil................................................................................................................................ 72 3.2.5 Basic Soil Properties.................................................................................................................... 72 3.3 Physical properties....................................................................................................................................... 72 3.3.1 Soil Texture.................................................................................................................................. 72 3.3.1.1 Characteristics of Soil Separates or Textural Classes................................................ 73 3.3.1.2 Methods of Textural Determination.......................................................................... 73 3.3.1.3 Determination of Textural Class by Textural Triangle.............................................. 74 3.3.1.4 Identifying Soil Texture by Measurement................................................................. 74 3.3.1.5 Assessment of Textural Classes by Feeling in Hand................................................. 74 3.3.1.6 Soil Texture and Management................................................................................... 76 3.3.2 Soil Structure............................................................................................................................... 76 3.3.2.1 Mechanism of Soil Aggregation................................................................................ 77 3.3.2.2 Aggregate Stability.................................................................................................... 77 3.3.2.3 Types of Structural Units........................................................................................... 77 3.3.2.4 Classification of Soil Structures................................................................................. 77 3.3.2.5 Grades of Soil Structure............................................................................................ 78 3.3.2.6 The Form (Type)........................................................................................................ 78 3.3.2.7 Size (Classes)............................................................................................................. 78 3.3.2.8 Types of Soil Morphological Structures.................................................................... 78 3.3.2.9 Factors Affecting Soil Structure................................................................................ 79 3.3.2.10 Significance of Soil Structure.................................................................................... 81 3.3.2.11 Effect of Soil Structure on Other Physical Properties............................................... 81 3.3.2.12 Why is Soil Structure So Important?......................................................................... 81 3.3.2.13 Role of Soil Structure in Relation to Plant Growth................................................... 81 3.3.2.14 Maintaining Soil Structure........................................................................................ 82 3.3.3 Soil Surface Area......................................................................................................................... 82 3.3.4 Soil Density.................................................................................................................................. 82 3.3.4.1 Particle Density.......................................................................................................... 82 3.3.4.2 Bulk Density.............................................................................................................. 82 3.3.4.3 Factors Affecting Bulk Density................................................................................. 83 3.3.5 Soil Colloids................................................................................................................................. 83 3.3.5.1 General Properties of Soil Colloids........................................................................... 83 3.3.5.2 Types of Soil Colloids................................................................................................ 85 3.3.6 Soil Porosity................................................................................................................................. 86 3.3.7 Consistence.................................................................................................................................. 86 3.3.8 Soil Color..................................................................................................................................... 87 3.3.8.1 Munsell Color System................................................................................................ 87 3.3.9 Soil Permeability......................................................................................................................... 88 3.3.10 Soil Compaction........................................................................................................................... 88 3.3.11 Soil Resistivity............................................................................................................................. 88 3.3.12 Soil Temperature and Heat.......................................................................................................... 88 3.4 Soil Water and Plant Relations.................................................................................................................... 88 3.5 Relationship to Drainage............................................................................................................................. 89 3.5.1 Soil Drainage Classes.................................................................................................................. 89 3.6 Soil Hydraulic Conductivity........................................................................................................................ 89 Summary................................................................................................................................................................ 89 Further Reading...................................................................................................................................................... 90 Chapter 4 Chemical Properties of Soil................................................................................................................................... 91 4.1 Introduction................................................................................................................................................. 91

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4.2 4.3 4.4 4.5 4.6 4.7

Chemical Properties of Soils....................................................................................................................... 91 Why Improve Chemical Properties of Soil?................................................................................................ 91 Colloidal Properties of Soils....................................................................................................................... 92 Origin of Charges in Soil and Ion Exchange............................................................................................... 92 Inorganic Components................................................................................................................................ 93 Interactions Among Soil Components........................................................................................................ 93 4.7.1 Soil Colloids................................................................................................................................. 93 4.7.1.1 Mineral Colloids........................................................................................................ 93 4.7.1.2 Organic Colloids........................................................................................................ 93 4.7.2 Adsorption of Ions....................................................................................................................... 94 4.8 Origin of Charges in Soil and Ion Exchange............................................................................................... 95 4.8.1 Exchange Capacity....................................................................................................................... 95 4.8.2 Cation Exchange Capacity........................................................................................................... 96 4.8.3 Factors Effecting CEC................................................................................................................. 96 4.8.4 Mechanism of Cation Exchange.................................................................................................. 96 4.8.5 Replacing Power of Cations......................................................................................................... 97 4.8.6 Base Saturation............................................................................................................................ 97 4.8.7 Forms and Functions of Base Cations......................................................................................... 97 4.8.7.1 Forms of the Base Cations......................................................................................... 97 4.8.7.2 Functions of the Base Cations.................................................................................... 97 4.8.7.3 Cycling of Base Cations............................................................................................. 97 4.8.7.4 Importance of Cation Exchange................................................................................ 98 4.8.7.5 Implications of CEC on Management........................................................................ 99 4.8.8 Anion Exchange Capacity........................................................................................................... 99 4.9 Soil pH......................................................................................................................................................... 99 4.9.1 Desirable Soil pH (pH Range) for Optimum Crop Production.................................................... 99 4.9.2 Factors Affecting Soil Acidity................................................................................................... 100 4.9.3 Sources of Basicity..................................................................................................................... 100 4.9.4 Effect of Soil pH on Plant Growth............................................................................................. 100 4.9.5 Soil Reaction...............................................................................................................................101 4.9.6 Method of Expressing Acidity or Alkalinity..............................................................................101 4.9.7 Buffering and Soil Reactions..................................................................................................... 102 4.9.8 Factors Controlling Soil Reactions............................................................................................ 102 4.9.9 Equilibrium and Buffering........................................................................................................ 103 4.10 Influence of Soil Reaction on Availability of Nutrients............................................................................ 103 4.10.1 Salt-Affected Soils..................................................................................................................... 105 4.10.2 Calcareous Soils......................................................................................................................... 105 4.10.3 Soil Acidity................................................................................................................................ 105 4.10.3.1 Origins of Soil Acidity............................................................................................. 105 4.10.3.2 Causes of Soil Acidity.............................................................................................. 106 4.10.3.3 Pools of Soil Acidity................................................................................................ 107 4.10.3.4 Problems Associated with Acidity........................................................................... 107 4.10.4 Management or Amelioration of Soil Acidity........................................................................... 107 4.10.5 Liming of the Soil...................................................................................................................... 108 4.10.5.1 Liming Materials..................................................................................................... 108 4.10.5.2 Use of Fluid and Pelletized Lime............................................................................ 108 4.10.6 Salty Soils.................................................................................................................................. 109 4.10.6.1 Salinization.............................................................................................................. 109 4.10.6.2 Soil Salinity............................................................................................................. 109 4.10.6.3 Crops and Saline Soils............................................................................................. 109 4.10.6.4 Sodic Soils................................................................................................................110 4.10.6.5 Improvement of Saline and Sodic Soils....................................................................110 4.10.6.6 Prevention of Salinization.........................................................................................110 4.10.6.7 Calcareous Soil.........................................................................................................111 4.11 Overall Improvements of Chemical Properties of Soil..............................................................................111 Summary...............................................................................................................................................................111 Further Reading.....................................................................................................................................................112

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Chapter 5 Introduction to Soil Water Systems.......................................................................................................................113 5.1 Introduction................................................................................................................................................113 5.2 Soil-Water System......................................................................................................................................113 5.3 Importance of Soil Water...........................................................................................................................113 5.4 The Interaction between Water and Soil Components...............................................................................114 5.5 Types of Soil Water....................................................................................................................................114 5.5.1 Physical Classification of Soil Water..........................................................................................114 5.5.1.1 Gravitational Water...................................................................................................114 5.5.1.2 Capillary Water.........................................................................................................114 5.5.1.3 Hygroscopic/Chemical Water...................................................................................115 5.5.2 Biological Classification of Soil Water.......................................................................................116 5.6 Soil Water Constants..................................................................................................................................116 5.6.1 Saturated Water (Zero)................................................................................................................116 5.6.2 Field Capacity.............................................................................................................................116 5.6.3 Wilting Coefficient......................................................................................................................116 5.6.4 Hygroscopic Coefficient..............................................................................................................116 5.6.5 Plant Available Water Capacity..................................................................................................116 5.6.6 Wilting Point...............................................................................................................................117 5.6.7 Oven Dry Moisture.....................................................................................................................117 5.6.8 Maximum WHC.........................................................................................................................118 5.6.9 Sticky Point Moisture.................................................................................................................118 5.7 Measuring Soil WHC.................................................................................................................................118 5.8 The Effects of Clay Particles in the Soil on Water Storage........................................................................118 5.9 Soil Moisture Tension.................................................................................................................................118 5.10 Available Water for Plants..........................................................................................................................118 5.10.1 Specific Problems and Causes for Poor Plant Functions............................................................118 5.10.2 Control Measures Taken to Increase Water Availability............................................................119 5.10.3 Measuring of AWC.....................................................................................................................119 5.10.3.1 Soil Composition.......................................................................................................119 5.10.3.2 Soil Profile............................................................................................................... 120 5.10.3.3 Influence of Soil Texture and Structure on Water Movement................................. 120 5.11 Entry of Water into the Soil and Storage................................................................................................... 121 5.11.1 Soil Permeability....................................................................................................................... 121 5.11.2 Infiltration.................................................................................................................................. 121 5.11.2.1 Infiltration Rate........................................................................................................ 121 5.11.2.2 Factors Influencing the Infiltration Rate.................................................................. 122 5.11.2.3 Depth of Penetration................................................................................................ 123 5.11.2.4 Percolation............................................................................................................... 123 5.11.3 Soil Water Movement................................................................................................................. 123 5.11.3.1 Soil Moisture Content.............................................................................................. 123 5.11.3.2 Levels of Soil Moisture Content.............................................................................. 123 5.11.3.3 Groundwater Table................................................................................................... 125 5.11.4 Ways to Retain Water in Soil..................................................................................................... 126 5.11.4.1 Cohesion and Adhesion Forces................................................................................ 126 5.11.4.2 Surface Tension........................................................................................................ 127 5.11.4.3 Polarity or Dipole Characteristics of Water............................................................. 127 5.11.4.4 Factors Affecting Soil Water Retention................................................................... 127 5.11.5 Soil Water Storage..................................................................................................................... 127 5.12 Sources of Water for Crop Growth............................................................................................................ 127 5.12.1 Rainfall...................................................................................................................................... 128 5.12.1.1 Effective Rainfall..................................................................................................... 128 5.12.1.2 Evapotranspiration (ET).......................................................................................... 128 5.12.2 Irrigation Water.......................................................................................................................... 129 5.12.2.1 Quality of Irrigation Water...................................................................................... 129 5.12.2.2 Carbonates............................................................................................................... 129 5.12.2.3 High Boron Water.................................................................................................... 130

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5.13 Soil Water Potential................................................................................................................................... 130 5.14 Irrigation Water Management................................................................................................................... 130 5.14.1 Measure of Soil Moisture...........................................................................................................131 5.14.2 Calculation of Soil Moisture Content by Mass and Volume..................................................... 132 5.14.3 Measuring Soil WHC................................................................................................................ 132 5.14.3.1 Soil Water Properties............................................................................................... 132 5.14.3.2 Depth of Water in the Field is Another Useful Quantity......................................... 132 5.14.3.3 Characteristic Curves Relate ψ to θ......................................................................... 132 5.14.3.4 Plant Available Water (PAW)................................................................................... 132 5.14.3.5 Each Soil has a Unique Available Water Capacity (AWC)...................................... 133 5.15 How Plants get Water from Soil................................................................................................................ 133 5.16 Methods of Water Applying to the Field................................................................................................... 134 5.16.1 Surface Irrigation....................................................................................................................... 134 5.16.2 Sprinkler Irrigation.................................................................................................................... 134 5.16.3 Drip Irrigation............................................................................................................................ 134 5.17 Soil Water Conservation............................................................................................................................ 134 5.17.1 Water Conservation Methods..................................................................................................... 134 5.17.1.1 Reducing Water Demand......................................................................................... 134 5.17.1.2 Mechanical Practices such as.................................................................................. 135 5.17.1.3 Watershed Approach................................................................................................ 135 5.17.1.4 Rainwater Harvesting.............................................................................................. 135 5.17.1.5 Agriculture............................................................................................................... 135 5.17.1.6 Water Conservation by Good Practices................................................................... 135 5.18 Effect of Soil Air on Soil Water................................................................................................................ 136 5.19 Drainage of Soil Water.............................................................................................................................. 136 5.19.1 Different Types of Drainage...................................................................................................... 136 5.19.2 Water Logging........................................................................................................................... 137 5.19.3 Soil Permeability and its Effect on Drainage............................................................................ 137 5.19.4 Features of a Well-Drained Soil................................................................................................ 137 5.19.5 What Factors Influence Soil Permeability?............................................................................... 137 5.19.5.1 Soil Type.................................................................................................................. 137 5.19.5.2 Soil Compaction....................................................................................................... 137 5.19.5.3 Soil Stability............................................................................................................ 138 5.19.5.4 Ground Cover and SOM.......................................................................................... 138 5.19.5.5 Vegetation Type and Land Use................................................................................ 138 5.19.5.6 Soil Aspect............................................................................................................... 138 5.19.6 How Does Soil Water Permeability Affect Soil Health?........................................................... 138 5.19.7 How do I Improve Soil Permeability?....................................................................................... 139 5.19.8 Profiting from Adequate Soil Permeability............................................................................... 140 5.19.9 Best Practices for the Management and Monitoring of Soil Drainage and Waterlogging........ 140 5.19.9.1 Dry Land Crops and Pastures.................................................................................. 140 5.19.9.2 Irrigated Crops and Pastures.................................................................................... 140 Summary...............................................................................................................................................................141 Further Reading.................................................................................................................................................... 142

Section II  Soil Management for Sustainable Agriculture Chapter 6 Healthy Soils for Sustainable Agriculture............................................................................................................ 145 6.1 Introduction............................................................................................................................................... 145 6.2 Soil Security for Sustainable Agriculture................................................................................................. 145 6.3 Healthy Soil Allows for Healthy Food and Healthy People...................................................................... 146 6.3.1 Healthy Soils for Healthy Plants................................................................................................ 146 6.3.2 Healthy Soil is Vital to Human Life on Earth........................................................................... 146 6.3.3 The Road to Healthy Soils......................................................................................................... 146

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6.4 6.5 6.6 6.7

6.8 6.9 6.10 6.11 6.12 6.13

6.14

6.15

6.16

Soil Provides Substances to Build Life......................................................................................................147 Composition of Healthy Soils and Plant Nutrients.....................................................................................147 Soil Texture and Structure Determines Soil Health.................................................................................. 149 What is Soil Health?.................................................................................................................................. 149 6.7.1 Soil Health Indicators................................................................................................................ 149 6.7.2 Microorganisms as Indicators of Soil Health............................................................................ 149 6.7.3 Important Characteristics of Healthy Soils............................................................................... 150 Healthy Soils for Sustainable Farming...................................................................................................... 151 Functions of Healthy Soils........................................................................................................................ 152 Methods to Develop Healthy Soils............................................................................................................ 153 6.10.1 What Can We Do to Develop Healthy Soils?............................................................................ 153 6.10.2 What Can Farmers Do to Maintain Healthy Soils?................................................................... 154 Soil Properties Rate-Limiting Factors....................................................................................................... 156 Healthy Farm Practices for Sustainable Agriculture................................................................................. 157 6.12.1 Soil as a System......................................................................................................................... 157 6.12.2 Soil as Habitat............................................................................................................................ 157 Factors Controlling Soil Health................................................................................................................. 158 6.13.1 Water.......................................................................................................................................... 158 6.13.2 Soil Type.................................................................................................................................... 158 6.13.3 Soil Organisms and Functions................................................................................................... 159 6.13.4 Carbon and Energy.................................................................................................................... 159 6.13.5 Nutrients..................................................................................................................................... 159 Healthy Farm Practices............................................................................................................................. 159 6.14.1 Aims of Healthy Farm Practices................................................................................................ 159 6.14.2 Qualities of Healthy Farm......................................................................................................... 160 6.14.3 Key Healthy Farm Practices...................................................................................................... 160 6.14.4 Healthy Farm Benefits............................................................................................................... 160 6.14.5 Helping of Farmers to Prosper by Healthy Farms..................................................................... 160 Role of Soil Enzymes in Maintaining Soil Health.................................................................................... 160 6.15.1 Soil Enzymes............................................................................................................................. 160 6.15.2 Origin and State of Soil Enzymes..............................................................................................161 6.15.3 Application of Soil Enzymes......................................................................................................161 6.15.4 Soil Enzymes as Indicators of Soil Health.................................................................................161 6.15.5 Role of Soil Enzymes in Maintaining Soil Health.....................................................................161 6.15.5.1 Amylase....................................................................................................................161 6.15.5.2 Arylsulfatases...........................................................................................................161 6.15.5.3 β-Glucosidase...........................................................................................................161 6.15.5.4 Cellulases................................................................................................................. 162 6.15.5.5 Chitinase.................................................................................................................. 162 6.15.5.6 Dehydrogenase......................................................................................................... 162 6.15.5.7 Phosphatases............................................................................................................ 162 6.15.5.8 Proteases.................................................................................................................. 162 6.15.5.9 Urease...................................................................................................................... 162 Good Agricultural Practices for Maintaining Healthy Soils.................................................................... 163 6.16.1 Description of the UN FAO GAPs............................................................................................. 163 6.16.2 GAPs Related to Soil................................................................................................................. 163 6.16.3 GAPs Related to Water.............................................................................................................. 163 6.16.4 USDA GAPs/GHP Program...................................................................................................... 163 6.16.5 Soil Quality Management: Key Strategies for Agricultural Land Management....................... 163 6.16.5.1 Enhance Organic Matter.......................................................................................... 164 6.16.5.2 Avoid Excessive Tillage........................................................................................... 164 6.16.5.3 Manage Pests and Nutrients Efficiently................................................................... 164 6.16.5.4 Prevent Soil Compaction......................................................................................... 164 6.16.5.5 Keep the Ground Covered....................................................................................... 164 6.16.5.6 Diversify Cropping Systems.................................................................................... 164 6.16.6 Improvement of Current Land Husbandry Practices................................................................. 164 6.16.6.1 Establish National Regulations for Sound Land Husbandry................................... 164

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6.16.6.2 Monitor Soil Health................................................................................................. 164 6.16.6.3 Build Capacity......................................................................................................... 165 6.16.6.4 Disseminate Information and Communicate Benefits............................................. 165 Summary.............................................................................................................................................................. 165 Further Reading.................................................................................................................................................... 165 Chapter 7 Soil Erosion and its Conservation........................................................................................................................ 167 7.1 Introduction............................................................................................................................................... 167 7.2 What is Soil Erosion?................................................................................................................................ 167 7.3 Erosion Process......................................................................................................................................... 167 7.4 Causes of Soil Erosion............................................................................................................................... 167 7.4.1 Land Use.................................................................................................................................... 168 7.4.2 Climate....................................................................................................................................... 168 7.4.3 Soil............................................................................................................................................. 168 7.4.4 Hydrology.................................................................................................................................. 168 7.4.5 Landforms.................................................................................................................................. 168 7.5 Types of Soil Erosion................................................................................................................................. 168 7.5.1 Geological or Natural Erosion................................................................................................... 169 7.5.2 Accelerated Erosion................................................................................................................... 169 7.5.3 Water Erosion............................................................................................................................. 169 7.5.3.1 Splash or Raindrop Erosion......................................................................................171 7.5.3.2 Sheet Erosion............................................................................................................171 7.5.3.3 Gully Erosion............................................................................................................171 7.5.3.4 Rill Erosion...............................................................................................................171 7.5.3.5 Stream Bank Erosion............................................................................................... 172 7.5.3.6 Tunnel Erosion......................................................................................................... 172 7.5.3.7 Tillage Erosion......................................................................................................... 172 7.5.3.8 Mud Flow Affecting the Sea.................................................................................... 172 7.5.3.9 Problems of Erosion................................................................................................. 172 7.5.3.10 Remedies to Combat Water Erosion........................................................................ 172 7.5.3.11 Remedies for Saving Cropland.................................................................................173 7.5.4 Wind Erosion..............................................................................................................................174 7.5.4.1 Mechanism of Wind Erosion....................................................................................174 7.5.4.2 Detachment...............................................................................................................174 7.5.4.3 Transportation...........................................................................................................175 7.5.4.4 Deposition.................................................................................................................175 7.5.4.5 Types of Wind Erosion.............................................................................................175 7.5.4.6 Effects of Wind Erosion............................................................................................175 7.5.4.7 Influencing Factors Affecting the Extent of Wind Erosion......................................175 7.5.4.8 Control of Wind Erosion...........................................................................................176 7.5.5 Other Types of Soil Erosion....................................................................................................... 177 7.5.5.1 Frost (Frozen-Melt erosion)..................................................................................... 177 7.5.6 Gravity....................................................................................................................................... 177 7.6 Properties Determining Soil Erodibility................................................................................................... 177 7.7 The Consequences of Soil Erosion.............................................................................................................178 7.7.1 Damages Caused by Soil Erosion...............................................................................................178 7.7.1.1 Economic and Environmental Effects of Soil Erosion............................................ 179 7.7.2 Soil Erosion and Climate Change.............................................................................................. 179 7.7.3 Tectonic Effects......................................................................................................................... 179 7.8 Conservation of Soil Erosion..................................................................................................................... 179 7.8.1 Erosion Control Options............................................................................................................ 179 7.8.2 Measuring Erosion..................................................................................................................... 180 7.8.3 Runoff Management and Erosion Control................................................................................. 180 7.8.4 Soil Conservation Methods........................................................................................................ 180 7.8.4.1 Increase of Vegetation.............................................................................................. 180 7.8.4.2 Mulch Farming.........................................................................................................181

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7.8.4.3 Conservation Tillage.................................................................................................181 7.8.4.4 Strip Cropping.......................................................................................................... 183 7.8.4.5 Contour Farming...................................................................................................... 183 7.8.4.6 Build Terraces.......................................................................................................... 183 7.8.4.7 Cover Crops............................................................................................................. 183 7.8.4.8 Crop Rotation........................................................................................................... 184 7.8.4.9 Windbreakers........................................................................................................... 184 7.8.4.10 Riparian Zones......................................................................................................... 184 7.8.4.11 Dam Building........................................................................................................... 184 7.8.5 Reforestation.............................................................................................................................. 184 7.8.6 Promotion of Soil Organisms.................................................................................................... 184 7.8.7 Good Farming Practices............................................................................................................ 184 Summary.............................................................................................................................................................. 185 Further Reading.................................................................................................................................................... 185 Chapter 8 Soil Pollution: Causes, Effects, and Preventive Measures................................................................................... 187 8.1 Introduction............................................................................................................................................... 187 8.2 Soil Contamination.................................................................................................................................... 187 8.3 Sources of Soil Pollutants.......................................................................................................................... 187 8.3.1 Agricultural Waste..................................................................................................................... 187 8.3.1.1 Fertilizer Contamination......................................................................................... 188 8.3.1.2 Pesticide Contamination.......................................................................................... 188 8.3.2 Industrial Waste......................................................................................................................... 189 8.3.3 Urban Waste............................................................................................................................... 189 8.3.4 Hazardous Wastes...................................................................................................................... 189 8.3.5 Organic Pollutants’ Different Origins....................................................................................... 189 8.4 Main Causes of Soil Pollution................................................................................................................... 190 8.4.1 Natural Pollutants...................................................................................................................... 190 8.4.2 Manmade Pollutants.................................................................................................................. 190 8.4.3 Dumping of Solid Wastes...........................................................................................................191 8.4.4 Deforestation.............................................................................................................................. 192 8.4.5 Pollution Due to Urbanization................................................................................................... 192 8.4.5.1 Pollution of Surface Soils........................................................................................ 192 8.4.5.2 Pollution of Underground Soil................................................................................. 193 8.4.6 Soil Pollution Examples............................................................................................................. 193 8.5 Bioavailability of Aged Xenobiotic Residues............................................................................................ 193 8.6 Sorption of Chemical Constituents in Soils.............................................................................................. 194 8.6.1 Principal Factors Governing Sorption in Soils.......................................................................... 195 8.6.2 Sorption of Organic Molecules.................................................................................................. 196 8.7 Effect of Soil Pollutants............................................................................................................................. 197 8.7.1 Effect on Agriculture................................................................................................................. 197 8.7.2 Effect on Plant Life.................................................................................................................... 197 8.7.3 Land Degradation...................................................................................................................... 197 8.7.4 Effect of Soil Pollutants on Human Health............................................................................... 198 8.7.5 Ecosystem Effects...................................................................................................................... 199 8.7.6 Air and Water Contamination.................................................................................................... 199 8.7.7 Long-Term Effects on the Environment.................................................................................... 199 8.7.8 Economic Losses....................................................................................................................... 199 8.8 Case Studies of Soil Pollution................................................................................................................... 199 8.9 Testing of Soil Pollution............................................................................................................................ 200 8.10 Remediation of Soil Pollution................................................................................................................... 200 8.10.1 Promote Bio Fertilizers.............................................................................................................. 200 8.10.2 Promote Use of Biopesticides and Fungicides........................................................................... 200 8.10.3 Reduce Toxic Waste................................................................................................................... 200 8.10.4 Reusing of Materials.................................................................................................................. 200 8.10.5 Recycling and Recovery of Materials........................................................................................ 201

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8.10.6 Reforesting................................................................................................................................. 201 8.10.7 Solid Waste Treatment............................................................................................................... 201 8.10.8 Alterations in Rhizosphere Microflora...................................................................................... 201 8.10.9 Biodegradation of Pesticides...................................................................................................... 201 8.11 Nonpoint Source Pollution (NPS)............................................................................................................. 202 8.11.1 Management of NPs Pollution................................................................................................... 202 8.11.1.1 In Agriculture.......................................................................................................... 202 8.11.1.2 Farmers’ Role in Management of NPs Pollution..................................................... 203 8.11.1.3 Household’s Level.................................................................................................... 204 8.11.1.4 Community Level.................................................................................................... 204 Summary.............................................................................................................................................................. 205 Further Reading.................................................................................................................................................... 206 Chapter 9 Soil Testing for Better Nutrient Management...................................................................................................... 207 9.1 Introduction............................................................................................................................................... 207 9.2 What is a Soil Test?................................................................................................................................... 207 9.3 Importance of Soil Test............................................................................................................................. 207 9.4 Field Tests-Soil Properties......................................................................................................................... 208 9.4.1 Soil Horizons and Depth............................................................................................................ 208 9.4.2 Organic Matter and Humus....................................................................................................... 208 9.4.3 Soil Texture................................................................................................................................ 208 9.4.4 Simple Test for Dispersibility.....................................................................................................210 9.4.5 Soil Structure and Porosity.........................................................................................................211 9.4.6 Soil Infiltration Test....................................................................................................................211 9.4.7 The Percolation Test in the Field................................................................................................211 9.4.8 Field Test: Soil Compaction........................................................................................................211 9.4.9 Soil Moisture...............................................................................................................................211 9.4.10 Soil Fertility................................................................................................................................211 9.4.11 Soil pH....................................................................................................................................... 212 9.4.12 Soil Life..................................................................................................................................... 212 9.5 Soil Analysis in the Laboratory................................................................................................................. 212 9.5.1 Obtaining Representative Soil Samples..................................................................................... 212 9.5.1.1 Equipments for Collecting Soil Samples................................................................. 213 9.5.1.2 The Effect of Soil Variability on Soil Sampling...................................................... 213 9.5.2 Types of Sampling Methods...................................................................................................... 213 9.5.2.1 Composite Soil Sampling........................................................................................ 213 9.5.2.2 Grid Soil Sampling.................................................................................................. 213 9.5.2.3 General Procedure for Sample Collection............................................................... 213 9.5.3 Time it Right...............................................................................................................................214 9.5.4 Number of Samples Required for Soil Testing...........................................................................214 9.5.5 Use Clean Sampling Equipment................................................................................................ 215 9.5.6 Drying the Sample..................................................................................................................... 215 9.5.7 How to Prepare Soil Samples for Submission........................................................................... 215 9.5.8 Fill Out an Information Sheet and Label the Sample Box Completely..................................... 215 9.5.9 Storage and Handling................................................................................................................ 215 9.5.10 Package the Sample Appropriately.............................................................................................216 9.6 Laboratory Testing Methods......................................................................................................................216 9.6.1 Soil Testing Laboratories............................................................................................................217 9.6.2 Receiving the Soil Test Report...................................................................................................217 9.6.3 Types of Soil-testing...................................................................................................................217 9.6.4 Soil Diagnosis.............................................................................................................................217 9.7 Plant Tissue Nutrient Analysis...................................................................................................................218 9.7.1 Tissue Sampling..........................................................................................................................218 9.7.2 Types of Tissue Analyses............................................................................................................218 9.7.2.1 Calibration................................................................................................................218 9.7.2.2 Calibration Experiment.............................................................................................219

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9.7.3

Nondestructive Tissue Tests........................................................................................................219 9.7.3.1 Chlorophyll Content Meters......................................................................................219 9.7.3.2 Chlorophyll Fluorometry..........................................................................................219 9.7.4 Field Experiments.......................................................................................................................219 9.7.5 Analytical Methods.....................................................................................................................219 9.7.5.1 Record Test...............................................................................................................219 9.7.5.2 Shear Test are Taken on Two Machines...................................................................219 9.7.6 Soil Test for Plant Nutrients....................................................................................................... 220 9.7.6.1 Test for Nitrogen...................................................................................................... 220 9.7.6.2 Test for Phosphorus.................................................................................................. 220 9.7.6.3 Test for Potassium.................................................................................................... 220 9.7.6.4 Test for Calcium, Magnesium, and Sodium............................................................. 220 9.7.6.5 Test for Micronutrients............................................................................................. 220 9.7.7 Interpreting Laboratory Results................................................................................................. 220 9.7.7.1 Nitrogen................................................................................................................... 221 9.7.7.2 Phosphorus............................................................................................................... 221 9.7.7.3 Potassium................................................................................................................. 221 9.7.7.4 Calcium and Magnesium......................................................................................... 221 9.7.7.5 Micronutrients.......................................................................................................... 222 9.8 Testing Soil Contaminants........................................................................................................................ 222 9.9 Soil Test Interpretation and Fertilizer Recommendations........................................................................ 222 9.9.1 Interpreting the Numbers on the Soil Test Report..................................................................... 222 9.9.2 Fertilizer Recommendations...................................................................................................... 223 9.9.3 Laboratory Differences.............................................................................................................. 223 9.10 Soil Test Kits............................................................................................................................................. 224 Summary.............................................................................................................................................................. 224 Further Reading.................................................................................................................................................... 225 Chapter 10 Soil Preparation and Tillage................................................................................................................................. 227 10.1 Introduction............................................................................................................................................... 227 10.2 Brief History of Plowing........................................................................................................................... 227 10.3 What is Plowing or Tillage?...................................................................................................................... 227 10.4 The Purpose of Land Preparation............................................................................................................. 228 10.4.1 Weed Control............................................................................................................................. 228 10.4.2 Incorporation of Organic Material............................................................................................ 228 10.4.3 Incorporation of Commercial Fertilizers and Lime.................................................................. 228 10.4.4 Development of a Proper Seedbed............................................................................................. 228 10.4.5 To Loosen the Soil..................................................................................................................... 228 10.4.6 Shape the Soil............................................................................................................................ 229 10.4.7 Soil Segregation......................................................................................................................... 229 10.4.8 Pest Control................................................................................................................................ 229 10.4.9 Erosion Prevention..................................................................................................................... 229 10.4.10 Improve the Tilth....................................................................................................................... 229 10.5 Methods of Land Preparation.................................................................................................................... 229 10.5.1 Land Preparation by Hand......................................................................................................... 229 10.5.2 Land Preparation by Equipments.............................................................................................. 229 10.6 Preparation of Soil for Sowing.................................................................................................................. 229 10.6.1 Plowing...................................................................................................................................... 229 10.6.2 Leveling..................................................................................................................................... 229 10.6.3 Manuring................................................................................................................................... 230 10.7 Types of Tillage Operations...................................................................................................................... 230 10.8 Preparatory Tillage.................................................................................................................................... 230 10.8.1 Primary Tillage.......................................................................................................................... 230 10.8.2 Secondary Tillage...................................................................................................................... 231 10.8.3 Layout of Seedbed and Sowing................................................................................................. 231 10.8.4 After Cultivation........................................................................................................................ 231

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10.9 Types of Tillage Systems........................................................................................................................... 231 10.9.1 Conventional Tillage.................................................................................................................. 231 10.9.2 Hand Tilling............................................................................................................................... 232 10.9.3 Conservation Tillage.................................................................................................................. 232 10.9.3.1 Advantages............................................................................................................... 233 10.9.3.2 Disadvantages.......................................................................................................... 233 10.9.3.3 Methods of Conservation Tillage............................................................................ 233 10.9.4 No Tillage/Zero Tillage............................................................................................................. 234 10.9.4.1 No-Tillage for Sustainable Agriculture.................................................................... 234 10.9.4.2 Influence of No-Tillage on Different Soil Properties.............................................. 235 10.9.4.3 Steps in No-Tillage Adoption.................................................................................. 236 10.9.4.4 Outlook on No-Tillage............................................................................................. 236 10.9.4.5 Advantages of Conservative Tillage........................................................................ 237 10.9.4.6 Disadvantages of Conservative Tillage.................................................................... 237 10.10 Soil Preparation Equipments..................................................................................................................... 237 10.10.1 Source of Energy Supply for Tillage Operations....................................................................... 237 10.10.1.1 Humans.................................................................................................................... 237 10.10.1.2 Animals.................................................................................................................... 237 10.10.1.3 Tractors and Other Machineries.............................................................................. 238 10.11 Soil Tillage Implements............................................................................................................................ 238 10.11.1 Primary Tillage Implements...................................................................................................... 238 10.11.1.1 Indigenous Plows..................................................................................................... 238 10.11.1.2 Animal Drawn Moldboard Plow............................................................................. 238 10.11.2 Moldboard Plow......................................................................................................................... 238 10.11.2.1 Types of Moldboard Plows...................................................................................... 239 10.11.2.2 Classification of Moldboard Plows.......................................................................... 239 10.11.2.3 Components or Parts of Moldboard Plow................................................................ 239 10.11.2.4 Moldboard Plow Bottom.......................................................................................... 239 10.11.2.5 Types of Landslide................................................................................................... 241 10.11.2.6 Moldboard Plow Accessories................................................................................... 241 10.11.3 Disc plow................................................................................................................................... 241 10.11.3.1 Advantages of Disc Plow......................................................................................... 241 10.11.3.2 Disadvantages of Disc Plow..................................................................................... 241 10.11.3.3 Types of Disc Plow.................................................................................................. 242 10.11.4 The Rotovator............................................................................................................................ 242 10.11.5 Chisel Plow................................................................................................................................ 242 10.11.6 Disc Tiller Development............................................................................................................ 242 10.11.6.1 Types of Disc Plows................................................................................................. 242 10.11.7 Rotary Tillers Development Throughout History...................................................................... 243 10.11.7.1 Types of Rotary Tillers............................................................................................ 243 10.11.7.2 Development............................................................................................................ 243 10.11.8 Plows.......................................................................................................................................... 244 10.11.9 Cultivators.................................................................................................................................. 244 10.11.10 Harrows...................................................................................................................................... 244 10.11.11 Puddlers..................................................................................................................................... 245 10.11.12 Bund Formers............................................................................................................................ 245 10.11.13 Bed Furrow Former................................................................................................................... 246 10.11.14 Ridger......................................................................................................................................... 246 10.11.14.1 Types of Ridgers...................................................................................................... 246 10.11.15 Terracer cum Leveler................................................................................................................. 246 10.11.16 Subsoiler..................................................................................................................................... 246 10.12 Secondary Tillage Implements.................................................................................................................. 246 10.12.1 Types of Secondary Tillage Implements................................................................................... 247 10.12.2 Secondary Tillage Implements Maintenance Tips.................................................................... 247 10.13 Pros and Cons of Tillage........................................................................................................................... 247 10.13.1 The Benefits of Tillage Include.................................................................................................. 247 10.13.2 Negative Effects of Tillage Include........................................................................................... 247

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10.14 Future of Soil Preparation Technology..................................................................................................... 248 Summary.............................................................................................................................................................. 248 Further Reading.................................................................................................................................................... 249 Chapter 11 Composting for Sustainable Agriculture.............................................................................................................. 251 11.1 Introduction............................................................................................................................................... 251 11.2 What is Compost?...................................................................................................................................... 251 11.3 Why Compost?.......................................................................................................................................... 251 11.4 Historical Perspective of Composting....................................................................................................... 251 11.5 Composting as “Microbial Farming”........................................................................................................ 252 11.6 The Composting Process........................................................................................................................... 252 11.7 Benefits of Using Compost........................................................................................................................ 253 11.7.1 Physical Benefits........................................................................................................................ 253 11.7.2 Chemical Benefits...................................................................................................................... 254 11.7.3 Biological Benefits..................................................................................................................... 255 11.7.4 Additional Benefits of Compost................................................................................................. 255 11.7.5 Disadvantages............................................................................................................................ 256 11.8 Ingredients Required for Composting Organisms.................................................................................... 256 11.9 SOM Dynamics and Soil Aggregation are Closely Linked...................................................................... 256 11.9.1 Carbon–Nitrogen Relationships................................................................................................. 256 11.9.2 Raw Material Quantity and Composition.................................................................................. 257 11.9.3 Shredding of Refuse.................................................................................................................. 258 11.9.4 Manure and Bedding................................................................................................................. 258 11.9.5 Composting Phases.................................................................................................................... 258 11.9.6 Organisms Involved in Composting.......................................................................................... 259 11.10 Decomposition Process............................................................................................................................. 260 11.10.1 Anaerobic Composting Process................................................................................................. 260 11.10.1.1 Anaerobic Digestion Technologies can be Categorized into Three System Components............................................................................................................. 261 11.10.1.2 Advantages of Anaerobic Composting.................................................................... 261 11.10.2 Aerobic Composting.................................................................................................................. 261 11.10.2.1 Some Basic Advantages of the Aerobic Composting.............................................. 261 11.10.2.2 Factors Affecting Aerobic Composting Process...................................................... 262 11.10.2.3 Techniques for Effective Aerobic Composting........................................................ 263 11.11 Different ways of Making Compost.......................................................................................................... 265 11.12 Simplified Guide to Compost Production................................................................................................. 265 11.13 Compost Preparation Methods.................................................................................................................. 266 11.13.1 Pit Method.................................................................................................................................. 266 11.13.2 Heap Method.............................................................................................................................. 266 11.13.3 Bangalore Method...................................................................................................................... 266 11.13.4 Indore Method............................................................................................................................ 267 11.13.5 Windrow Composting................................................................................................................ 267 11.13.6 Synthetic Composting................................................................................................................ 267 11.13.7 Leaf Composting....................................................................................................................... 267 11.13.8 Bokashi Composting.................................................................................................................. 268 11.14 Organic Compost Tea................................................................................................................................ 268 11.14.1 Compost Tea Production............................................................................................................ 268 11.14.2 Manure Tea Preparation............................................................................................................. 268 11.14.3 Herbal Tea Preparation.............................................................................................................. 268 11.15 Liquid Manures......................................................................................................................................... 268 11.15.1 Hügelkultur................................................................................................................................ 268 11.15.2 Humanure.................................................................................................................................. 268 11.15.3 Industrial systems...................................................................................................................... 269 11.16 Compost..................................................................................................................................................... 269 11.16.1 Compost from Food Processing Wastes.................................................................................... 269 11.16.2 Compost from Livestock Manure.............................................................................................. 269

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11.16.3 Gobar Gas Slurry....................................................................................................................... 269 11.16.4 Compost from Crop By-Products.............................................................................................. 269 11.16.5 Enrichment of Compost............................................................................................................. 270 11.17 Biochar...................................................................................................................................................... 270 11.18 Vermiculture and Vermicompost.............................................................................................................. 271 11.18.1 Biology of Earthworms.............................................................................................................. 271 11.18.2 Earthworm Types....................................................................................................................... 271 11.18.3 Earthworm Reproduction........................................................................................................... 271 11.18.4 Digestion System of Earthworms.............................................................................................. 272 11.18.5 Earthworm Locomotion Improves the Soil Aeration and Mixing............................................. 272 11.18.6 Encouraging of Earthworm Activity......................................................................................... 272 11.18.7 Method of Large-scale Vermicompost Preparation................................................................... 272 11.18.8 Large-Scale Multiplication of Worms....................................................................................... 272 11.18.9 Creating a Good Environment for Earthworms......................................................................... 272 11.18.10 Harvesting the Worms............................................................................................................... 273 11.18.11 Benefits of Earthworms to the Agriculture................................................................................ 273 11.18.12 Advantages of Vermicomposting............................................................................................... 274 11.18.13 What to Avoid in Composting................................................................................................... 274 11.18.14 Monitoring and Record Keeping............................................................................................... 274 11.18.15 Troubleshooting......................................................................................................................... 274 11.19 Application of Zeolite in Sustainable Agriculture.................................................................................... 275 11.20 Green Fertilizer made from Weeds and Water......................................................................................... 276 Summary.............................................................................................................................................................. 277 Further Reading.................................................................................................................................................... 278 Chapter 12 Organic Farming and Precision Agriculture for Sustainable Farming................................................................ 279 12.1 Introduction............................................................................................................................................... 279 12.2 History of Organic Farming...................................................................................................................... 279 12.3 Organic Farming....................................................................................................................................... 279 12.3.1 Principles of Organic Farming.................................................................................................. 280 12.3.2 The Basic Components of Organic Farming............................................................................. 280 12.3.3 Use of OM.................................................................................................................................. 280 12.3.4 Indicators of Soil OM................................................................................................................ 281 12.3.5 Functions of OM in Soil............................................................................................................ 281 12.3.6 Distribution of SOM.................................................................................................................. 281 12.3.7 Nonhumic Substances: Significance and Function.................................................................... 281 12.4 Compounds and Functions of Humus....................................................................................................... 282 12.4.1 Humus Formation...................................................................................................................... 282 12.4.2 Mechanisms of Humus Formation............................................................................................. 283 12.4.2.1 Decomposition......................................................................................................... 283 12.4.2.2 Synthesis.................................................................................................................. 283 12.4.3 Benefits of Humus...................................................................................................................... 283 12.5 Organic Farming Methods........................................................................................................................ 283 12.5.1 Soil Management....................................................................................................................... 283 12.5.2 Weed Management.................................................................................................................... 284 12.5.3 Controlling Pests by Naturally Occurring Pesticides................................................................ 284 12.5.3.1 Predatory Mites are Effective for Controlling other Mites..................................... 284 12.5.3.2 Natural Antimicrobial Compounds......................................................................... 285 12.5.4 Disease Management in Organic Farming................................................................................ 285 12.5.5 Multicultural Farming............................................................................................................... 285 12.5.5.1 Crop Diversity.......................................................................................................... 285 12.5.5.2 Crop Rotation for Increased Productivity................................................................ 285 12.5.6 Exclusion of GM Crops in Organic Farming............................................................................. 285 12.6 Standards for Organic Agriculture............................................................................................................ 286 12.6.1 Standards for Composting......................................................................................................... 286

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12.6.2 Economics of Organic Farming................................................................................................. 286 12.6.3 Productivity and Profitability..................................................................................................... 286 12.6.4 Sustainability (African Case)..................................................................................................... 286 12.6.5 Employment Impact................................................................................................................... 287 12.6.6 Externalities............................................................................................................................... 287 12.6.7 Reduction/Elimination of Pesticides Use.................................................................................. 287 12.6.8 Food Quality and Safety............................................................................................................ 287 12.6.9 Soil Conservation....................................................................................................................... 287 12.6.10 Mitigation of Climate Change................................................................................................... 288 12.6.11 Reduction of Nutrient Leaching................................................................................................ 288 12.6.12 Conservation of Biodiversity..................................................................................................... 288 12.7 Sales and Marketing.................................................................................................................................. 288 12.7.1 Distributors for Organically Grown Produce............................................................................ 288 12.7.2 Farmers’ Markets....................................................................................................................... 288 12.7.3 Capacity Building...................................................................................................................... 288 12.7.4 Controversy................................................................................................................................ 289 12.8 Benefits of Organic Farming..................................................................................................................... 289 12.8.1 Consumer Benefits..................................................................................................................... 289 12.8.2 Advantages to the Farmers........................................................................................................ 290 12.8.3 Advantages of Organic Farming to the World........................................................................... 290 12.8.4 Environmental Benefits of Organic Agriculture........................................................................ 291 12.8.4.1 Sustainability Over the Long Term......................................................................... 291 12.8.4.2 Soil Nourishment..................................................................................................... 291 12.8.4.3 Water Quality and Storage....................................................................................... 291 12.8.4.4 Air............................................................................................................................ 291 12.8.4.5 Biodiversity.............................................................................................................. 291 12.8.4.6 GMOs....................................................................................................................... 292 12.8.4.7 Ecological Services.................................................................................................. 292 12.8.5 Disadvantages of Organic Farming........................................................................................... 292 12.9 Maintenance of Soil Fertility.................................................................................................................... 293 12.10 Organic versus Inorganic Foods................................................................................................................ 293 12.10.1 Advantages Organic Food......................................................................................................... 293 12.10.2 Disadvantages of Organic Foods............................................................................................... 294 12.11 What Does Organic Mean?....................................................................................................................... 294 12.11.1 The Legal Definition of Organic Certification.......................................................................... 294 12.11.2 Certified Organics...................................................................................................................... 294 12.11.3 The Organic Ethics.................................................................................................................... 294 12.11.4 Organic Farming is More About Common Sense..................................................................... 295 12.11.5 Exporting Organic Materials..................................................................................................... 295 12.11.6 Limitations, Potential, and Challenges of Organic Farming..................................................... 295 12.11.7 Organic Policies and Recommendations (in case of India)....................................................... 295 12.12 Precision Agriculture: A Robust Technology for Sustainable Agriculture............................................... 296 12.12.1 Potential of Precision Farming.................................................................................................. 297 12.12.2 How it Is Done?.......................................................................................................................... 297 12.12.3 Technologies used in Precision Agriculture.............................................................................. 297 12.12.4 Equipment, Methods, and Technology Supporting of Precision Agriculture........................... 298 12.12.4.1 AutoSteer................................................................................................................. 298 12.12.4.2 Light Bar Guidance Systems................................................................................... 298 12.12.4.3 Differential GPS...................................................................................................... 298 12.12.4.4 Commercial Differential GPS................................................................................. 298 12.12.4.5 Nationwide Differential GPS................................................................................... 298 12.12.4.6 Wide Area Augmentation System............................................................................ 298 12.12.4.7 Real Time Kinematic............................................................................................... 298 12.12.4.8 Grid Sampling.......................................................................................................... 298 12.12.4.9 Directed Sampling................................................................................................... 298 12.12.4.10 Management Zones.................................................................................................. 298

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12.12.4.11 Remote Sensing....................................................................................................... 299 12.12.4.12 Variable Rate Application........................................................................................ 299 12.12.4.13 Cloud Applications for Monitoring Fields............................................................... 299 12.12.4.14 Yield Monitoring Systems....................................................................................... 299 12.12.4.15 Mapping and Data Collection.................................................................................. 299 12.12.5 Emerging Technologies.............................................................................................................. 299 12.12.5.1 Global Positioning System (GPS) Receivers............................................................ 299 12.12.5.2 Mobile Devices........................................................................................................ 299 12.12.5.3 Cloud Applications for Monitoring Fields............................................................... 299 12.12.5.4 Robotics................................................................................................................... 299 12.12.5.5 Irrigation Monitoring............................................................................................... 300 12.12.5.6 Remote Sensing (RS)............................................................................................... 300 12.12.5.7 Drones and Satellite Imagery.................................................................................. 300 12.12.5.8 Variable-Rate Seeding............................................................................................. 300 12.12.5.9 Weather Modeling.................................................................................................... 300 12.12.5.10 Nitrogen Modeling................................................................................................... 301 12.12.5.11 Standardization........................................................................................................ 301 12.12.6 Internet of Things (IoT) and Big Data are the Future of Farming............................................. 301 12.12.7 The Building Blocks of a Precision Agriculture System........................................................... 302 12.12.8 Phytomonitoring........................................................................................................................ 302 12.12.8.1 Role of Phytomonitoring in Modern Agriculture.................................................... 303 12.13 Nanotechnology: A Novel Solution for Precision Agriculture.................................................................. 304 12.13.1 Application of Nanotechnology................................................................................................. 304 12.13.1.1 Nanoscale Carriers................................................................................................... 304 12.13.1.2 Microfabricated Xylem Vessels............................................................................... 304 12.13.1.3 Nanolignocellulosic Materials................................................................................. 305 12.13.1.4 Clay Nanotubes........................................................................................................ 305 12.13.1.5 Photocatalysis.......................................................................................................... 305 12.13.1.6 Bioremediation of Resistant Pesticides.................................................................... 305 12.13.1.7 Disinfectants............................................................................................................ 305 12.13.1.8 Wastewater Treatment.............................................................................................. 305 12.13.1.9 Nanobarcode Technology........................................................................................ 305 12.13.1.10 Quantum Dots (QDs) for Staining Bacteria............................................................. 306 12.13.1.11 Biosensors................................................................................................................ 306 12.13.1.12 Gold Nanoparticles.................................................................................................. 306 12.13.1.13 Smart Dust............................................................................................................... 306 12.13.1.14 ZigBee a Mesh Networking Standard..................................................................... 306 12.13.2 Systems for Sustainable Intensification in Agriculture.............................................................. 307 12.13.3 Systems to Improve the Quality of the Soil............................................................................... 307 12.13.4 Nanomaterials as Agents to Stimulate Plant Growth................................................................ 307 12.13.5 Nanomaterials used in Crop Production.................................................................................... 307 12.13.6 Nanodevices for the Management of the Food Supply Chain................................................... 307 12.13.7 Automation of Irrigation Systems.............................................................................................. 308 12.13.7.1 Nanotechnologies for Water Quality and Availability............................................. 308 12.13.8 Food Industry............................................................................................................................. 309 12.13.9 Nanomaterials from Plants........................................................................................................ 309 12.13.10 Nanotechnologies in Animal Production and Health Care....................................................... 309 12.13.10.1 Improving Feeding Efficiency and Nutrition........................................................... 309 12.13.10.2 Zoonotic Diseases.....................................................................................................310 12.13.10.3 Animal Reproduction and Fertility..........................................................................310 12.13.10.4 Animal Product Quality, Value, and Safety.............................................................310 12.13.10.5 Nanotechnology and Animal Waste Management...................................................310 12.13.11 Green Nanotechnology...............................................................................................................310 12.13.12 The Role of Good Governance and Policies for Effective Nanotechnology Development........311 12.13.13 Identification of Gaps and Obstacles..........................................................................................311 Summary...............................................................................................................................................................312 Further Reading.....................................................................................................................................................313

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Section III  Plant Nutrients and Biopesticides Chapter 13 Plant Mineral Nutrients.........................................................................................................................................317 13.1 Introduction................................................................................................................................................317 13.1.1 Where do Plant Nutrients Come from in Natural Ecosystems?.................................................317 13.1.2 Dynamics of Nutrient Cycle.......................................................................................................317 13.1.3 Plant Nutrition: Fertility or Nutrition.........................................................................................318 13.2 Classification of Plant Nutrients.................................................................................................................318 13.2.1 Nonmineral or Structural Nutrients............................................................................................319 13.2.2 Essential Versus Beneficial.........................................................................................................319 13.2.2.1 Essential Mineral Nutrients..................................................................................... 320 13.2.2.2 Beneficial Elements................................................................................................. 320 13.3 Macronutrients and Micronutrients........................................................................................................... 320 13.3.1 Macronutrients........................................................................................................................... 321 13.3.1.1 Primary Macronutrients........................................................................................... 321 13.3.1.2 Secondary Macronutrients....................................................................................... 321 13.3.2 Micronutrients............................................................................................................................ 322 13.3.3 Role of Mineral Nutrients in Crop Development....................................................................... 322 13.3.4 Primary Macronutrients............................................................................................................. 322 13.4 Nitrogen..................................................................................................................................................... 322 13.4.1 Source of Nitrogen to Plants...................................................................................................... 322 13.4.2 Mechanism of Nitrogen Assimilation in Plants......................................................................... 322 13.4.3 Functions Nitrogen in Plants...................................................................................................... 322 13.4.4 Nitrogen Deficiency................................................................................................................... 323 13.4.5 Nitrogen Available in Different Forms...................................................................................... 323 13.4.6 Nitrogen Cycle........................................................................................................................... 323 13.4.7 Nitrogen Fixation....................................................................................................................... 324 13.4.8 Nitrogen Mineralization in Soils............................................................................................... 325 13.4.9 Conditions Affecting Nitrogen Mineralization.......................................................................... 325 13.4.10 Immobilization........................................................................................................................... 325 13.4.11 Mineralization or Immobilization?............................................................................................ 325 13.4.12 Management of Organic Residues............................................................................................. 326 13.4.13 Nitrification................................................................................................................................ 326 13.4.14 Factors Affecting Nitrification................................................................................................... 326 13.4.15 Environmental Considerations................................................................................................... 326 13.4.16 Gaseous Losses of Nitrogen....................................................................................................... 326 13.4.16.1 Denitrification.......................................................................................................... 326 13.4.16.2 Volatilization............................................................................................................ 327 13.4.16.3 Nitrogen Exchange and Nitrate Leaching................................................................ 327 13.4.17 Management of Soil Acidification Due to Nitrogen Fertilizers................................................. 327 13.5 Phosphorus................................................................................................................................................ 327 13.5.1 Phosphorus Forms and Functions.............................................................................................. 328 13.5.1.1 Forms of Phosphorus Available for Plant Uptake.................................................... 328 13.5.1.2 Functions of Phosphorus in Plants........................................................................... 328 13.5.2 Phosphorus Deficiency............................................................................................................... 328 13.5.3 Phosphorus Cycle....................................................................................................................... 328 13.5.4 Phosphorus Uptake by Plant Roots............................................................................................ 328 13.5.4.1 Factors Affecting P-Sorption................................................................................... 330 13.5.4.2 Factors Decreasing P-Sorption................................................................................ 330 13.5.5 Solubility of Phosphate Minerals............................................................................................... 330 13.5.6 Mineralization and Immobilization of Phosphate..................................................................... 330 13.5.7 Management of Phosphorus: P-Fixation.................................................................................... 330 13.6 Potassium....................................................................................................................................................331 13.6.1 Potassium Nutrient Functions.....................................................................................................331 13.6.2 Potassium in Soils.......................................................................................................................331

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13.6.2.1 Unavailable Potassium..............................................................................................331 13.6.2.2 Slowly Available Potassium..................................................................................... 332 13.6.2.3 Readily Available Potassium................................................................................... 332 13.6.3 Potassium Deficiency................................................................................................................. 332 13.6.3.1 Common Potassium Symptoms............................................................................... 332 13.6.3.2 Correction of Potassium Deficiency........................................................................ 332 13.6.4 Sources of Potassium................................................................................................................. 332 13.7 Secondary Nutrients and Plant Growth..................................................................................................... 332 13.7.1 Calcium...................................................................................................................................... 333 13.7.1.1 Nutrient Functions................................................................................................... 333 13.7.1.2 Calcium Deficiency.................................................................................................. 334 13.7.2 Magnesium................................................................................................................................. 334 13.7.2.1 Nutrient Functions................................................................................................... 334 13.7.2.2 Magnesium Deficiency............................................................................................ 334 13.7.3 Sulfur......................................................................................................................................... 335 13.7.3.1 Nutrient Functions................................................................................................... 335 13.7.3.2 Sulfur Deficiency..................................................................................................... 335 13.8 Micronutrients........................................................................................................................................... 335 13.8.1 Boron.......................................................................................................................................... 335 13.8.1.1 Nutrient Functions................................................................................................... 335 13.8.1.2 Boron Source and Availability................................................................................. 336 13.8.1.3 Boron Deficiency..................................................................................................... 336 13.8.1.4 Boron Toxicity......................................................................................................... 336 13.8.1.5 Boron Cycle............................................................................................................. 336 13.8.1.6 Recommended Crops............................................................................................... 337 13.8.2 Copper........................................................................................................................................ 337 13.8.2.1 Nutrient Functions................................................................................................... 337 13.8.2.2 Copper Source and Availability............................................................................... 337 13.8.2.3 Copper Deficiency................................................................................................... 337 13.8.2.4 Copper Cycle............................................................................................................ 337 13.8.3 Iron............................................................................................................................................. 337 13.8.3.1 Iron Uptake by Plants.............................................................................................. 338 13.8.3.2 Nutrient Functions................................................................................................... 338 13.8.3.3 Iron Source and Availability.................................................................................... 338 13.8.3.4 Iron Deficiency......................................................................................................... 338 13.8.3.5 Iron Cycle................................................................................................................. 338 13.8.3.6 Managing Iron Deficiencies..................................................................................... 338 13.8.4 Manganese................................................................................................................................. 338 13.8.4.1 Nutrient Functions................................................................................................... 338 13.8.4.2 Manganese Source and Availability........................................................................ 339 13.8.4.3 Manganese Deficiency............................................................................................. 339 13.8.4.4 Manganese Cycle..................................................................................................... 339 13.8.4.5 Manganese Toxicity................................................................................................. 339 13.8.5 Molybdenum.............................................................................................................................. 339 13.8.5.1 Nutrient Functions................................................................................................... 340 13.8.5.2 Molybdenum Deficiency.......................................................................................... 340 13.8.5.3 Source and Availability............................................................................................ 340 13.8.5.4 Molybdenum Toxicity.............................................................................................. 340 13.8.5.5 Molybdenum Cycle.................................................................................................. 340 13.8.6 Zinc............................................................................................................................................ 340 13.8.6.1 Nutrient Functions................................................................................................... 340 13.8.6.2 Zinc Source and Availability................................................................................... 341 13.8.6.3 Zinc Deficiency........................................................................................................ 341 13.8.6.4 Zinc Cycle................................................................................................................ 341 13.9 Elements with Beneficial Effects............................................................................................................... 341 13.9.1 Chloride..................................................................................................................................... 341 13.9.1.1 Nutrient Functions................................................................................................... 341

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13.9.1.2 Chlorine Deficiency................................................................................................. 341 13.9.1.3 Chlorine Toxicity..................................................................................................... 342 13.9.2 Sodium....................................................................................................................................... 342 13.9.2.1 Nutrient Functions................................................................................................... 342 13.9.2.2 Essentiality of Sodium............................................................................................. 342 13.9.3 Nickel......................................................................................................................................... 342 13.9.3.1 Nutrient Functions................................................................................................... 342 13.9.4 Silicon........................................................................................................................................ 342 13.9.4.1 Nutrient Functions................................................................................................... 342 13.9.5 Vanadium................................................................................................................................... 343 13.9.6 Cobalt......................................................................................................................................... 343 13.9.7 Aluminum.................................................................................................................................. 343 13.9.8 Selenium.................................................................................................................................... 343 13.9.9 Arsenic....................................................................................................................................... 343 13.10 Nutrient Mobility....................................................................................................................................... 343 13.10.1 Within Plant............................................................................................................................... 343 13.10.2 Within Soil................................................................................................................................. 344 13.11 Environmental Influence on Nutritional Uptake....................................................................................... 344 13.11.1 Temperature............................................................................................................................... 344 13.11.2 Light Intensity and Duration...................................................................................................... 344 13.11.3 Humidity.................................................................................................................................... 344 13.12 Forms of Nutrients in the Soil................................................................................................................... 344 13.12.1 Mineralization versus Immobilization....................................................................................... 345 13.12.2 Effect of C:N (Carbon to Nitrogen) Ratios on Soil Mineralization/Immobilization................. 345 13.13 Signs of Faulty Nutrition in Plants............................................................................................................ 345 13.13.1 Symptoms of Individual Elemental Deficiencies....................................................................... 345 13.13.2 Nutrient Deficiency or Toxicity Symptoms............................................................................... 346 13.13.3 Toxic Effects of Mineral Elements............................................................................................ 348 13.13.4 Nutrient Interactions in Plants and Soils................................................................................... 349 13.14 Nutrient Management................................................................................................................................ 350 13.14.1 Nutrient Management Plan........................................................................................................ 350 13.14.2 Critical Nutrient Levels...............................................................................................................351 13.14.3 Relative Nutrient Status..............................................................................................................351 13.15 Plant Nutrient Application......................................................................................................................... 352 13.16 Nutrient Conservation in the Soil.............................................................................................................. 352 13.17 Untapped Nutrient Sources....................................................................................................................... 352 13.18 Genetic Engineering to Generate Internal Nutrient Sources.................................................................... 352 13.19 Benefits of Integrated Nutrient Management............................................................................................ 353 13.20 Nutrient Removal Values for Field Crops.................................................................................................. 353 13.21 Nutrient Management Guidelines for Individual Crops............................................................................ 353 13.22 Nutrient use Efficiency Improvement........................................................................................................ 353 13.22.1 Effective Nutrient use Efficiency Improvement......................................................................... 353 13.22.2 Nutrient use Efficiency.............................................................................................................. 354 Summary.............................................................................................................................................................. 354 Further Reading.................................................................................................................................................... 355 Chapter 14 Chemical Fertilizers and Fertigation................................................................................................................... 357 14.1 Introduction............................................................................................................................................... 357 14.2 Types of Fertilizers.................................................................................................................................... 357 14.2.1 Classification of Inorganic Fertilizers....................................................................................... 357 14.2.1.1 Based on Number of Nutrients Present.................................................................... 358 14.2.1.2 Blends (Mixed Fertilizers)....................................................................................... 358 14.2.1.3 Special Purpose Fertilizers...................................................................................... 360 14.3 Liquid Fertilizers....................................................................................................................................... 360 14.4 Organic Verses Inorganic Fertilizers........................................................................................................ 360 14.4.1 Organic Fertilizers..................................................................................................................... 360

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14.4.2 Inorganic or Synthetic Fertilizers.............................................................................................. 361 14.5 Advantages and Disadvantages of Chemical Fertilizers........................................................................... 361 14.5.1 Advantages of Chemical Fertilizers.......................................................................................... 361 14.5.2 Disadvantages of Chemical Fertilizers...................................................................................... 362 14.6 Chemical Fertilizer Production Process.................................................................................................... 362 14.7 Fertilizer Grade or Composition............................................................................................................... 363 14.8 Classification of Fertilizers Based on Particular Plant Nutrient Element................................................. 363 14.8.1 Nitrogenous Fertilizers.............................................................................................................. 363 14.8.1.1 Commercially Available Nitrogen Fertilizers.......................................................... 363 14.8.1.2 Sodium Nitrates....................................................................................................... 363 14.8.1.3 Ammonium Sulfate.................................................................................................. 364 14.8.1.4 Ammonium Nitrate.................................................................................................. 364 14.8.1.5 Ammonium Sulfate Nitrate..................................................................................... 364 14.8.1.6 Ammonium Phoshate.............................................................................................. 364 14.8.1.7 Ammonium Chloride............................................................................................... 364 14.8.1.8 Urea.......................................................................................................................... 364 14.8.1.9 Ammonia................................................................................................................. 365 14.8.1.10 Calcium Nitrate........................................................................................................ 365 14.8.1.11 Calcium Ammonium Nitrate................................................................................... 365 14.8.1.12 Potassium Nitrate..................................................................................................... 365 14.8.1.13 Organic Nitrogenous Fertilizers.............................................................................. 365 14.8.2 Phosphate Fertilizers................................................................................................................. 365 14.8.2.1 Rock Phosphate (RP)............................................................................................... 365 14.8.2.2 Super Phosphate....................................................................................................... 365 14.8.2.3 Basic Slag................................................................................................................. 366 14.8.2.4 Bonemeal................................................................................................................. 366 14.8.3 Potassium Fertilizers.................................................................................................................. 366 14.8.3.1 Sources of Potassium............................................................................................... 366 14.8.4 Secondary Nutrient Fertilizers.................................................................................................. 367 14.8.4.1 Calcium.................................................................................................................... 367 14.8.4.2 Magnesium............................................................................................................... 367 14.8.4.3 Sulfur....................................................................................................................... 367 14.8.5 Micronutrients............................................................................................................................ 367 14.8.5.1 Iron Fertilizers......................................................................................................... 367 14.8.5.2 Zinc.......................................................................................................................... 367 14.8.5.3 Copper...................................................................................................................... 368 14.8.5.4 Manganese............................................................................................................... 368 14.8.5.5 Boron........................................................................................................................ 368 14.8.5.6 Molybdenum Carrying Fertilizers........................................................................... 368 14.9 Problems Associated with use of Inorganic Fertilizers............................................................................. 368 14.9.1 Trace Mineral Depletion............................................................................................................ 368 14.9.2 Over-Fertilization....................................................................................................................... 368 14.9.3 High Energy Consumption........................................................................................................ 368 14.9.4 Long-Term Sustainability.......................................................................................................... 368 14.9.5 Water Quality............................................................................................................................. 368 14.9.5.1 Eutrophication.......................................................................................................... 368 14.9.5.2 Blue Baby Syndrome............................................................................................... 368 14.9.6 Soil............................................................................................................................................. 369 14.9.6.1 Soil Acidification..................................................................................................... 369 14.9.6.2 Persistent Organic Pollutants................................................................................... 369 14.9.6.3 Heavy Metal Accumulation..................................................................................... 369 14.9.6.4 Radioactive Element Accumulation......................................................................... 369 14.9.7 Atmosphere................................................................................................................................ 369 14.9.8 Other Problems.......................................................................................................................... 369 14.10 Mode and Time of Application of Fertilizers and Manures...................................................................... 369 14.11 Diagnosing the Fertilizer Needs of Soils.................................................................................................. 370

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14.11.1 Nutrient Deficiency Symptoms of Plants................................................................................... 370 14.11.2 Plant Analysis............................................................................................................................ 370 14.11.3 Biological Methods.................................................................................................................... 370 14.11.3.1 Field Experiments.................................................................................................... 370 14.11.3.2 Indicator Plants........................................................................................................ 370 14.11.3.3 Microbiological Test................................................................................................ 370 14.11.3.4 Laboratory and Green House Tests......................................................................... 370 14.11.4 Chemical Analysis of Soils (Soil Testing)................................................................................. 371 14.11.5 Modern Approaches of Soil Fertility Evaluation and Fertilizer Recommendation.................. 371 14.11.5.1 Soil Test Crop Response (STCR)............................................................................. 371 14.11.5.2 Adjustment Equations.............................................................................................. 371 14.11.5.3 Advantages of STCR............................................................................................... 372 14.12 Diagnosis and Recommendation Integrated System (DRIS Method)....................................................... 372 14.13 Fertilizer Calculations............................................................................................................................... 372 14.13.1 Fertilizer Labeling..................................................................................................................... 372 14.13.2 Fertilizer Application Calculations............................................................................................ 373 14.13.3 Organic Sources......................................................................................................................... 373 14.13.4 Application or Placement of Fertilizers..................................................................................... 373 14.14 Fertilizing.................................................................................................................................................. 373 14.14.1 Timing of Fertilizer Application................................................................................................ 373 14.14.2 How Much Fertilizer to Apply................................................................................................... 374 14.14.3 Mode of Fertilizer Delivery to Plants........................................................................................ 374 14.15 Methods of Fertilizer Placement/Application........................................................................................... 375 14.15.1 Application of Fertilizers in Solid form..................................................................................... 375 14.15.1.1 Broadcasting............................................................................................................ 375 14.15.1.2 Advantages of Broadcasting.................................................................................... 376 14.15.1.3 Disadvantages of Broadcasting................................................................................ 376 14.15.1.4 How to Broadcast Fertilizer Evenly......................................................................... 376 14.15.2 Placement................................................................................................................................... 376 14.15.2.1 Practice of Fertilizers Placement............................................................................. 376 14.15.2.2 Different Methods of Placement.............................................................................. 376 14.15.3 Top Dressing.............................................................................................................................. 377 14.15.4 Side-Dressing............................................................................................................................. 377 14.15.5 Pellet Application....................................................................................................................... 377 14.15.6 Seed Cum Fertilizer Drill.......................................................................................................... 377 14.15.7 Perforating................................................................................................................................. 377 14.16 Application of Liquid Fertilizers............................................................................................................... 377 14.16.1 Liquid Form of Fertilizers is Applied by the Following Methods............................................. 377 14.16.1.1 Starter Solutions....................................................................................................... 378 14.16.1.2 Foliar Feeding.......................................................................................................... 378 14.16.1.3 Fertilizers Mix......................................................................................................... 378 14.16.1.4 Injection into Soil..................................................................................................... 378 14.16.1.5 Fertigation................................................................................................................ 379 14.16.2 Types of Fertigation................................................................................................................... 379 14.16.3 Aerial Application...................................................................................................................... 379 14.16.4 Wetting Agents.......................................................................................................................... 380 14.16.5 Soil versus Foliar Fertilizer Application.................................................................................... 380 14.16.6 Best Practice for Foliar Spraying............................................................................................... 380 14.16.7 Mineral Deficiency Spraying..................................................................................................... 381 14.16.8 Guidelines for Foliar Spraying................................................................................................... 381 14.16.9 Organic Manure Placement....................................................................................................... 381 14.17 Tips to get Best Efficiency of Applied Fertilizers..................................................................................... 382 14.18 Importance of Achieving the Right Nutrient Balance.............................................................................. 382 14.18.1 Law of the Minimum................................................................................................................. 382 14.18.2 Timing of Fertilizer Application................................................................................................ 382 14.18.3 Growth Stages............................................................................................................................ 383

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14.18.4 Keeping Good Records.............................................................................................................. 383 14.18.5 Follow Soil Specialists’ Recommendations............................................................................... 384 14.18.6 Why Practice Nutrient Management in Farming?..................................................................... 384 Summary.............................................................................................................................................................. 384 Further Reading.................................................................................................................................................... 386 Chapter 15 Organic Fertilizers............................................................................................................................................... 387 15.1 Introduction............................................................................................................................................... 387 15.2 Discussion of the Term “Organic”............................................................................................................ 387 15.3 Chemical versus Organic.......................................................................................................................... 387 15.4 Role of Carbon in Maintaining Soil Health and Sustaining the Soil Biological Community.................. 387 15.5 Organic Fertilizers and their Usage.......................................................................................................... 388 15.5.1 Examples of Organic Fertilizers................................................................................................ 389 15.5.2 Plant-Based Organic Fertilizers................................................................................................. 389 15.5.2.1 Alfalfa Meal............................................................................................................. 389 15.5.2.2 Corn Gluten Meal.................................................................................................... 389 15.5.2.3 Cottonseed Meal...................................................................................................... 389 15.5.2.4 Molasses................................................................................................................... 389 15.5.2.5 Soybean Meal.......................................................................................................... 389 15.5.2.6 Oil Cakes................................................................................................................. 390 15.5.2.7 Neem Cake Fertilizer............................................................................................... 390 15.5.2.8 Kelp Meals (Seaweed)............................................................................................. 390 15.5.2.9 Humus...................................................................................................................... 391 15.5.2.10 Peat Moss................................................................................................................. 391 15.5.3 Animal-Based Fertilizers........................................................................................................... 391 15.5.3.1 Bone Meal................................................................................................................ 391 15.5.3.2 Blood Meal............................................................................................................... 391 15.5.3.3 Fish Emulsion.......................................................................................................... 391 15.5.3.4 Earthworm Castings (Worm Excrements)............................................................... 392 15.5.3.5 Feather Meal............................................................................................................ 392 15.5.3.6 Animal Manures...................................................................................................... 392 15.6 Mineral Fertilizers..................................................................................................................................... 392 15.6.1 Epsom Salts................................................................................................................................ 392 15.6.2 Chilean Nitrate of Soda............................................................................................................. 393 15.6.3 Calcitic (Limestone)................................................................................................................... 393 15.6.4 Dolomite (Limestone)................................................................................................................ 393 15.6.5 Calcium...................................................................................................................................... 393 15.6.6 Gypsum (hydrated calcium sulfate)........................................................................................... 393 15.6.7 Hard Rock Phosphate................................................................................................................. 393 15.6.8 Soft-Rock Phosphate.................................................................................................................. 393 15.6.9 Rock Dusts (or Stone Meal)....................................................................................................... 393 15.6.10 Green Sand................................................................................................................................. 393 15.6.11 Rock Potash/Potassium.............................................................................................................. 393 15.6.12 Langbeinite, Sold Under the Brand Name Sul-Po-Mag............................................................ 393 15.6.13 Sulfur......................................................................................................................................... 394 15.6.14 Wood Ash.................................................................................................................................. 394 15.7 Microorganisms......................................................................................................................................... 394 15.8 Cow Manure.............................................................................................................................................. 394 15.9 Compost..................................................................................................................................................... 394 15.10 Treated Sewage Sludge.............................................................................................................................. 394 15.11 Urine.......................................................................................................................................................... 394 15.12 Blended Fertilizer...................................................................................................................................... 394 15.13 Contents and Best Practices...................................................................................................................... 395 15.13.1 Manures and Composts.............................................................................................................. 395 15.13.2 Green Manure............................................................................................................................ 395 15.13.3 Plant, Stubble, and Root Residues............................................................................................. 396

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15.13.4 Other Fertilizers......................................................................................................................... 396 15.14 Benefits of Organic Fertilizers.................................................................................................................. 396 15.14.1 Benefits of Organic Fertilizers................................................................................................... 396 15.14.2 Disadvantages............................................................................................................................ 397 15.15 Key Role of Carbon in Maintaining Soil Health and Sustaining Soil Biological Community................. 398 15.16 Natural or Homemade Organic Fertilizers................................................................................................ 398 15.16.1 Banana Peels.............................................................................................................................. 398 15.16.2 Coffee Grounds.......................................................................................................................... 398 15.16.3 Eggshells.................................................................................................................................... 398 15.16.4 Seaweed..................................................................................................................................... 399 15.16.5 Weeds......................................................................................................................................... 399 15.16.6 Molasses..................................................................................................................................... 399 15.16.7 Human Urine............................................................................................................................. 399 15.16.8 Grass Clippings.......................................................................................................................... 399 15.16.9 Cat and Dog Food...................................................................................................................... 399 15.16.10 Green Tea................................................................................................................................... 399 15.16.11 Hair............................................................................................................................................ 399 15.16.12 Manure....................................................................................................................................... 399 15.16.13 Others......................................................................................................................................... 400 15.16.13.1 Cornmeal................................................................................................................. 400 15.16.13.2 How to Make Worm Poo or Worm Castings Tea.................................................... 400 15.17 Are Organic Fertilizers Worth the Extra Cost?......................................................................................... 400 15.17.1 Why go Organic?....................................................................................................................... 400 15.17.2 Precautions................................................................................................................................. 401 15.17.3 Quickest Rate of Released Nutrients......................................................................................... 401 15.17.4 Using Organic Fertilizers Blends............................................................................................... 401 15.17.5 Dry Organic Fertilizers.............................................................................................................. 401 15.17.6 Liquid Organic Fertilizers......................................................................................................... 401 15.17.6.1 Applying Liquid Fertilizers..................................................................................... 401 15.18 Using Growth Enhancers.......................................................................................................................... 402 15.18.1 Applying Growth Enhancers..................................................................................................... 402 15.18.2 Panchagavya—Organic Growth Stimulant............................................................................... 402 15.18.2.1 Ingredients............................................................................................................... 402 15.18.2.2 Panchagavya Preparation—Step-by-Step................................................................ 402 15.18.2.3 How to use Panchagavya......................................................................................... 403 15.18.2.4 Uses of Panchagavya................................................................................................ 403 15.18.2.5 Effects of Panchagavya on Plants............................................................................ 403 Summary.............................................................................................................................................................. 403 Further Reading.................................................................................................................................................... 404 Chapter 16 Biofertilizers for Integrated Nutrient Management.............................................................................................. 405 16.1 Introduction............................................................................................................................................... 405 16.2 Biofertilizers.............................................................................................................................................. 405 16.2.1 What are Biofertilizers?............................................................................................................. 405 16.2.2 How do Biofertilizers Work?..................................................................................................... 406 16.2.3 What is the Need for Use of Biofertilizers?............................................................................... 406 16.3 Special Advantages and Disadvantages of Biofertilizers.......................................................................... 407 16.3.1 Benefits/Advantages Biofertilizers............................................................................................. 407 16.3.2 Disadvantages............................................................................................................................ 407 16.4 Types of Biofertilizers and their Description............................................................................................ 407 16.4.1 Classification of Biofertilizers................................................................................................... 408 16.4.2 A Portfolio of Biofertilizers Methods........................................................................................ 408 16.5 Nitrogen Fixing Biofertilizers................................................................................................................... 409 16.5.1 Symbiotic Nitrogen Fixing Bacteria...........................................................................................410 16.5.2 Diversity Among Root Nodule Bacteria.....................................................................................410 16.5.3 Genetic Basis for Nodulation and Nitrogen Fixation..................................................................410

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16.6

16.7

16.8

16.9

16.5.4 Rhizobium...................................................................................................................................410 16.5.5 The Colonization Process...........................................................................................................410 16.5.5.1 Signaling...................................................................................................................411 16.5.5.2 Infection Thread Formation......................................................................................412 16.5.5.3 Nodule Development.................................................................................................412 16.5.5.4 Nitrogen Fixation......................................................................................................412 16.5.5.5 Nitrogenase Complex................................................................................................412 16.5.5.6 Nitrogenease (A 220 kD heterotetramer)..................................................................413 16.5.5.7 Seed Treatment.........................................................................................................414 16.5.5.8 Amount of Atmospheric Nitrogen Fixed Varies with Different Crops and Bacterial Strains........................................................................................................414 16.5.6 Frankia........................................................................................................................................414 16.5.7 Algal Biofertilizers.....................................................................................................................415 16.5.7.1 Blue-Green Algae (BGA).........................................................................................415 16.5.7.2 Azolla........................................................................................................................415 16.5.7.3 Microalagae Biomass as Biofertilizer.......................................................................417 16.5.7.4 Spirogyra...................................................................................................................417 16.5.8 Nonsymbiotic (NS) N2 fixation...................................................................................................417 16.5.8.1 Associative Nitrogen Fixation...................................................................................417 16.5.8.2 Herbspirillum............................................................................................................417 16.5.8.3 Azospirillum.............................................................................................................417 16.5.9 Free Living Nitrogen Fixers........................................................................................................419 16.5.9.1 Azotobactor...............................................................................................................419 16.5.9.2 Acetobactor...............................................................................................................419 Nutrient Solubilizing Microorganisms.......................................................................................................419 16.6.1 Phosphate Solubilizers (Phosphobacteria)..................................................................................419 16.6.2 Phosphate Solubilizers have Many Advantages......................................................................... 420 16.6.3 Sulfur Solubilizing Microbes..................................................................................................... 420 16.6.4 Silicate Solubilizing Bacteria (SSB).......................................................................................... 420 Nutrient Mobilizers................................................................................................................................... 420 16.7.1 Mycorrhizal Associations.......................................................................................................... 421 16.7.1.1 Types of Mycorrhizae.............................................................................................. 421 16.7.1.2 Benefits of Mycorrhizal Biofertilizers..................................................................... 421 16.7.1.3 Mechanism of Action............................................................................................... 422 16.7.1.4 Factors Influence...................................................................................................... 422 16.7.2 Potash Mobilizer........................................................................................................................ 422 16.7.2.1 Benefits of Potash Mobilizers.................................................................................. 422 16.7.2.2 Advantages............................................................................................................... 423 16.7.3 Zinc Mobilizers.......................................................................................................................... 423 Plant Growth Promoting Biofertilizers..................................................................................................... 424 16.8.1 Enzymatic Biofertilizer.............................................................................................................. 424 16.8.2 Phytohormones.......................................................................................................................... 424 16.8.3 Organic Waste Decomposers..................................................................................................... 425 16.8.4 Homemade Biofertilizers........................................................................................................... 425 16.8.4.1 Compost Tea Basic Recipe....................................................................................... 425 16.8.4.2 Preparation Compost Extract................................................................................... 425 16.8.4.3 Using Compost Tea or Extract................................................................................. 425 16.8.4.4 Starter Solution........................................................................................................ 426 16.8.4.5 Amara Leaf Extract................................................................................................. 426 16.8.4.6 Fermented Buttermilk and Coconut milk Solution................................................. 426 16.8.4.7 Panchakavya............................................................................................................ 426 Saprophytes/Compost Biofertilizers.......................................................................................................... 426 16.9.1 Production Technology.............................................................................................................. 426 16.9.2 Isolation and Identification of Strains........................................................................................ 427 16.9.3 Upscaling of Biomass................................................................................................................ 427 16.9.4 Impregnation of Carrier with Fully Grown Microbial Broth or Immobilization of Grown Cells to Obtain Liquid Formulations............................................................................. 428

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16.9.5 Preparation of Carrier-Based Formulations............................................................................... 428 16.9.6 Preparation of Liquid Formulations........................................................................................... 428 16.9.7 Caution to be Taken while Using Liquid Biofertilizers............................................................. 428 16.10 Production of Biofertilizers....................................................................................................................... 428 16.10.1 General Steps of Biofertilizer Production.................................................................................. 429 16.10.2 Equipment Required for Biofertilizer Production..................................................................... 429 16.11 Mass Production of Bacterial Biofertilizers.............................................................................................. 429 16.11.1 Culturing of Microorganisms.................................................................................................... 429 16.11.1.1 Procedure................................................................................................................. 430 16.11.1.2 Inoculum Preparation.............................................................................................. 430 16.11.2 Carrier Material and Processing.................................................................................................431 16.11.2.1 The Properties of Carrier Material...........................................................................431 16.11.2.2 Preparation of Carrier Material................................................................................431 16.11.3 Mixing the Carrier and the Broth Culture and Packing.............................................................431 16.11.3.1 Preparation of Inoculants Packet..............................................................................431 16.11.4 Schematic Representation of Mass Production of Bacterial Biofertilizers................................431 16.11.4.1 Specification of the Polythene Bags..........................................................................431 16.11.4.2 Storage of Biofertilizer Packet..................................................................................431 16.12 Mass Production of Mycorrhizal Biofertilizer...........................................................................................431 16.12.1 Method of Production................................................................................................................ 432 16.12.2 Application of AM Fungi.......................................................................................................... 432 16.13 Mass Production and Field Application of Cyanobacteria........................................................................ 432 16.13.1 Multiplication in Trays............................................................................................................... 432 16.13.2 Multiplication Under Field Condition........................................................................................ 432 16.13.3 Method of Inoculation of BGA in Rice Field............................................................................ 433 16.14 Mass Production and Field Application of Azolla.................................................................................... 433 16.14.1 Mass Multiplication of Azolla Under Field Conditions............................................................. 433 16.14.2 Inoculation of Azolla to Rice Crop............................................................................................ 433 16.15 Inoculation Methods.................................................................................................................................. 434 16.16 How to Make BioFertilizer (Panchagavyam)............................................................................................ 434 16.17 Methods of Biofertilizer Application........................................................................................................ 434 16.17.1 Seed Treatment or Seed Inoculation.......................................................................................... 434 16.17.2 Seedling Root Dipping.............................................................................................................. 435 16.17.3 Main Field Application.............................................................................................................. 435 16.17.4 Self Inoculation or Inoculation Tubers...................................................................................... 435 16.17.5 Mixed Inoculants....................................................................................................................... 435 16.18 Guidelines on Buying and Storage of Biofertilizers.................................................................................. 435 16.18.1 Precautions to Take Using while Biofertilzers.......................................................................... 436 16.19 Marketing Aspects..................................................................................................................................... 436 16.20 Constraints in Biofertilizer Technology.................................................................................................... 436 16.20.1 Technological Constraints and Poor Acceptability................................................................... 436 16.20.2 Poor Quality Unsterile Carrier is the Biggest Constraint.......................................................... 437 16.20.3 Infrastructural Constraints........................................................................................................ 437 16.20.4 Financial Constraints................................................................................................................. 437 16.20.5 Environmental Constraints........................................................................................................ 437 16.20.6 Human Resources and Quality Constraints............................................................................... 437 16.20.7 Marketing Constraints and Requirements................................................................................. 437 Summary.............................................................................................................................................................. 437 Further Reading.................................................................................................................................................... 438 Chapter 17 Biopesticides for Integrated Pest Management.................................................................................................... 439 17.1 Introduction............................................................................................................................................... 439 17.2 Pesticides................................................................................................................................................... 439 17.2.1 Benefits of Chemical Pesticides................................................................................................. 439 17.2.2 Chemical Pesticides and their Ill Effects on the Environment.................................................. 440 17.2.3 Hazards of Pesticide Use........................................................................................................... 441

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17.3

17.4

17.5

17.6 17.7 17.8 17.9

17.2.3.1 Direct Impact on Humans........................................................................................ 441 17.2.3.2 Impact through Food Commodities......................................................................... 441 17.2.3.3 Impact on Environment........................................................................................... 441 17.2.3.4 Surface Water Contamination.................................................................................. 441 17.2.3.5 Groundwater Contamination................................................................................... 441 17.2.3.6 Soil Contamination.................................................................................................. 441 17.2.3.7 Effect on Beneficial Soil Microorganisms............................................................... 442 17.2.3.8 Contamination of Air, Soil, and Nontarget Vegetation........................................... 442 17.2.3.9 Nontarget Organisms............................................................................................... 442 Alternatives to Chemical Pesticides.......................................................................................................... 442 17.3.1 Crop Scouting............................................................................................................................ 443 17.3.1.1 Preparation............................................................................................................... 443 17.3.1.2 Field History............................................................................................................ 443 17.3.1.3 Equipments.............................................................................................................. 443 17.3.1.4 Scouting Frequency................................................................................................. 443 17.3.1.5 Scouting Patterns..................................................................................................... 443 17.3.1.6 Scouting Report....................................................................................................... 443 Use of Biopesticides for Sustainable Agriculture...................................................................................... 443 17.4.1 What are Biopesticides.............................................................................................................. 443 17.4.2 Mode of Action of Biopesticides............................................................................................... 444 17.4.3 The Potential for Biopesticides.................................................................................................. 444 17.4.4 Advantages of Using Biopesticides and Biocontrol Agents....................................................... 444 17.4.4.1 Advantages............................................................................................................... 444 17.4.4.2 Disadvantages.......................................................................................................... 444 17.4.5 Types of Biopesticides and Biocontrol Agents.......................................................................... 445 17.4.6 Some Examples of Biocontrols Developed in More Recent Years............................................ 445 17.4.6.1 Biological Insecticides............................................................................................. 445 17.4.6.2 Biological Fungicides............................................................................................... 445 17.4.6.3 Viricides................................................................................................................... 446 17.4.6.4 Plant-Based.............................................................................................................. 446 Microbial Pesticides.................................................................................................................................. 446 17.5.1 Bacillus Thuringiensis (Bt)........................................................................................................ 446 17.5.1.1 Cry Protein Mode of Action.................................................................................... 447 17.5.1.2 Mechanism of Resistance Development.................................................................. 447 17.5.1.3 How to Prevent Resistance Development................................................................ 447 17.5.2 Agrobacterium Radiobacter (Agrocin)...................................................................................... 447 17.5.3 Pseudomonas Fluorescens (Phenazine)..................................................................................... 448 17.5.4 Fungicides.................................................................................................................................. 448 17.5.4.1 Trichoderma............................................................................................................. 448 17.5.4.2 Benefits.................................................................................................................... 449 17.5.5 Viral Biopesticides..................................................................................................................... 449 17.5.5.1 Baculoviruses........................................................................................................... 449 17.5.6 Protozoans.................................................................................................................................. 450 17.5.7 Entomopathogenic Fungi—in Insect Control............................................................................ 451 17.5.7.1 Beauveria Bassiana.................................................................................................. 451 17.5.7.2 Verticillium Lecanii................................................................................................. 452 17.5.7.3 Pheromone Traps for Insect Pest Management........................................................ 452 17.5.7.4 Practical use of Pheromones.................................................................................... 453 17.5.7.5 Mode of Pheromone Application............................................................................. 454 17.5.7.6 Things You Should Know about Trapping.............................................................. 454 17.5.7.7 Targets Insects......................................................................................................... 454 Plant-Incorporated Protectants (PIPs)....................................................................................................... 454 Botanical Pesticides................................................................................................................................... 454 Biochemical Pesticides.............................................................................................................................. 454 17.8.1 Azadirachtin Pesticide (Neem-Based)....................................................................................... 455 Biotic Agents/Natural Enemies................................................................................................................. 456 17.9.1 Predators.................................................................................................................................... 456

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17.9.2 Parasitoids.................................................................................................................................. 456 17.9.3 Trichogramma............................................................................................................................ 457 17.9.4 Protozoans.................................................................................................................................. 458 17.9.5 Insect Parasitic Nematodes........................................................................................................ 458 17.10 RNAi Biopesticides................................................................................................................................... 459 17.11 Inoculants.................................................................................................................................................. 459 17.12 Advances Biopesticide Production............................................................................................................ 459 17.13 Bio and Biopesticides................................................................................................................................ 460 17.13.1 Farmers’ Perspectives in using Biopesticide and Bio (IPM) in Agriculture in India................ 460 17.13.2 Safety Testing of Microbials...................................................................................................... 460 17.13.3 Routes of Hazards...................................................................................................................... 460 17.13.4 Three-Tier Testing...................................................................................................................... 460 Summary.............................................................................................................................................................. 461 Further Reading.................................................................................................................................................... 461

Section IV  Soil Organisms in Sustainable Agriculture Chapter 18 Soil Biology Management for Sustainable Soil Health........................................................................................ 465 18.1 Introduction............................................................................................................................................... 465 18.2 Soil Biology............................................................................................................................................... 465 18.3 Soil Biota and its Importance.................................................................................................................... 466 18.4 Biodiversity and Biomass of Soils............................................................................................................. 466 18.5 Size Classification of Soil Organisms....................................................................................................... 468 18.5.1 Soil Flora.................................................................................................................................... 468 18.5.1.1 Soil Microflora (0.001–0.02 mm)............................................................................ 468 18.5.1.2 Soil Macroflora (wide range of species)................................................................... 469 18.5.2 Soil Fauna.................................................................................................................................. 469 18.5.2.1 Microfauna (