Legumes : physiology and molecular biology of abiotic stress tolerance

Main subject categories: • Legumes • Molecular biology of legumes • Physiology of legumes • Abiotic stress tolerance of legumes • Genomics of legumes • Genetics of legumesThis edited volume provides state-of–the-art overview of abiotic stress responses and tolerance mechanisms of different legume crops viz., chickpea, mung bean, lentil, black gram, cowpea, cluster bean, soybean and groundnut.Legumes play an important role in human nutrition and soil health through fixation of nitrogen. Legume production and productivity are vulnerable to different abiotic stresses. A proper understanding about the physiological and molecular basis of the legume crops is essential for genetic improvement of abiotic stress tolerance. This book consists of 15 chapters covering physiological and biochemical basis, molecular physiology, molecular breeding, genetics, genomics, transgenics, epigenetics of drought, saline, high temperature and nutrient deficiency stresses, and the role of microRNAs in abiotic stress tolerance.This volume offers new perspectives in legume crop abiotic stress management, and is useful for various stakeholders, including postgraduate students, scientists, environmentalists and policymakers. Preface Contents Editors and Contributors 1: Physiology and Molecular Biology of Abiotic Stress Tolerance in Legumes 1.1 Introduction 1.2 Abiotic Stress 1.3 Drought-Stress Response and Signaling 1.4 Temperature Stress 1.5 Heavy Metal Tolerance 1.6 Saline/Salt Tolerance 1.7 Flood Tolerance 1.8 Conclusion References 2: Harnessing Genetic Variation in Physiological and Molecular Traits to Improve Heat Tolerance in Food Legumes 2.1 Introduction 2.2 Heat Stress and Legumes 2.3 Growth-Based Studies 2.3.1 Biomass 2.3.2 Plant Height 2.3.3 Root System Architecture 2.4 Yield-Based Traits 2.4.1 Seed Number 2.4.2 Seed Weight 2.5 Pollen Grain Traits 2.6 Leaf-Based Parameters 2.6.1 Stomatal Conductance 2.6.2 Stay-Green Trait 2.6.3 Chlorophyll Fluorescence 2.6.4 Photosynthetic Rate 2.6.5 Sucrose 2.6.6 Cell Membrane Thermostability 2.6.7 Canopy Temperature Depression 2.7 Biochemical Traits 2.7.1 Oxidative Stress and Antioxidants 2.7.2 Metabolites 2.7.3 Heat-Shock Proteins 2.8 Genes for Heat Tolerance 2.9 Scope of Harnessing Germplasm for Designing Heat Tolerance 2.10 Genetics of Heat Tolerance 2.11 Genomic Resources for Heat Tolerance 2.12 Transcriptomics for Unfolding Candidate Genes for Heat Tolerance 2.13 Proteomics and Metabolomics Resolving Gene Networks for Heat Tolerance in Grain Legumes 2.14 Conclusions References 3: Traits Associated with Drought and High-Temperature Stress and Its Associated Mechanisms in Legumes 3.1 Introduction 3.2 Traits Associated with Drought and High Temperature (HT) Stress Tolerance and Its Phenotyping Method 3.2.1 Green Leaf Area Duration 3.2.2 Plant Water Status 3.2.3 Canopy Temperature Depression 3.2.4 Limited Transpiration 3.2.5 Root Architecture 3.2.6 Membrane Stability 3.2.7 Photochemical Efficiency 3.2.8 Yield-Forming Traits 3.3 Conclusion References 4: Epigenetics of Abiotic Stress Tolerance in Legumes 4.1 Introduction 4.2 Epigenetics and Major DNA Methylation Mechanisms 4.2.1 De Novo Methylation 4.2.2 Maintenance of Methylation 4.2.3 DNA Demethylation 4.3 Methylation of Various Regions of the Gene 4.3.1 Histone Modifications 4.3.2 Noncoding RNAs and Epigenetic Regulation Under Abiotic Stress 4.4 Epigenetics and Abiotic Stress Tolerance in Legumes 4.4.1 Temperature-Stress Tolerance 4.4.1.1 Heat Stress 4.4.1.2 Chilling Stress 4.4.2 Drought-Stress Tolerance 4.4.3 Salinity-Stress Tolerance 4.4.4 Abiotic Stress Tolerance and DNA Demethylation 4.4.5 Abiotic Stress Tolerance and Epigenetics-Based Breeding Strategies in Legumes 4.5 Conclusions and Future Prospects References 5: Morphophysiological and Molecular Diversity in Mung Bean (Vigna radiata L.) 5.1 Introduction 5.2 Origin 5.3 Genetic Resources 5.4 Cultivation 5.5 Genetic Variability 5.6 Mutation 5.6.1 Mutations Induced Through Physical Factors 5.6.2 Mutations Induced Through Chemical Factors 5.6.3 Mutations Induced Through Physical and Chemical Factors 5.7 Genotype x Environment Interaction and Stability 5.8 Correlation and Path Analysis 5.9 Genetic Divergence 5.10 Plant Protection 5.10.1 Viral Diseases 5.10.2 Fungal Diseases 5.10.3 Bacterial Diseases 5.10.4 Nematodes 5.10.5 Insect Pests 5.11 Physiology and Abiotic Stresses 5.11.1 Water Stress and Drought 5.11.2 Salt Stress 5.11.3 Other Abiotic Stresses 5.12 Tissue Culture and Genetic Transformation 5.13 Genetic Markers and Biotechnology 5.14 Conclusion and Prospects References 6: Molecular Characterization and Mapping of Stress Resistance Genes Using SNP Platform in Legumes 6.1 Introduction to Legumes 6.1.1 Stress Resistance in Legumes 6.1.2 Tolerance 6.1.3 Resistance 6.2 Breeding Strategies for Characterization of Stress Resistance Genes 6.2.1 Germplasm Characterization 6.3 Genetic Analysis and Selection Methods for Stress Resistance in Legumes 6.3.1 Screening Methods 6.3.2 Marker-Assisted Genomic Selection 6.3.3 Gene Postulation 6.3.4 Genetic Analysis 6.4 Population Development 6.4.1 Development of Mapping Population 6.5 Molecular Breeding of Legumes in Genomics Era 6.5.1 Molecular Markers for Selection of Stress-Resistant Genes 6.6 High-Throughput Technology and SNP Discovery 6.6.1 Sequencing for SNP discovery 6.6.2 First-Generation DNA Sequencing 6.6.3 Next-Generation Sequencing (NGS) 6.6.4 SNP Genotyping and Validation 6.7 Molecular Mapping of Stress Resistance Gene(s)/QTL(s) Using SNP Markers 6.7.1 Genetic Maps of Legumes 6.8 Mapping a Gene or QTL 6.8.1 Oligo-Gene Mapping (Single-Gene Mapping) 6.8.1.1 Bulked Segregant Analysis (BSA) 6.8.1.2 Selective Genotyping 6.8.1.3 Bulked Segregant RNA-Seq (BSR-Seq) 6.8.1.4 Single-Gene Mapping Procedure 6.9 QTL Mapping 6.9.1 Mapping a QTL(s): Procedure 6.10 Marker-Assisted Backcrossing and Gene Pyramiding 6.10.1 Marker-Assisted Backcrossing 6.10.2 Gene Pyramiding References 7: Genomics of Abiotic Stress in Rice bean (Vigna umbellata) 7.1 Introduction 7.2 Genetic Resources of Rice bean 7.3 Physiology and Genetics of Abiotic Stress 7.4 Genomic Resources in Rice bean 7.4.1 Genome Sequences 7.4.2 Molecular Markers and Transcriptomes 7.4.3 Genetic Linkage Maps 7.5 Status and Opportunities of Genomic Research for Abiotic Stress in Rice bean 7.6 Future Perspectives References 8: Genetics and Genomics of Drought and Heat Tolerance in Cowpea, Mung Bean and Black Gram 8.1 Introduction 8.2 Independent and Collective Effects of Drought and Heat Stress 8.3 Genetic Variability for Heat and Drought Tolerance 8.4 Genetics of Heat and Drought Tolerance 8.5 Breeding Strategies for Improving Drought and Heat Tolerance 8.6 Screening of Target Traits for Drought- and Heat-Stress Tolerance 8.7 Genomics for Improving Drought and Heat Tolerance 8.7.1 Quantitative Trait Locus (QTL) Mapping 8.7.2 Association Studies 8.7.3 Comparative Genomics 8.7.4 Candidate Genes 8.7.5 Genes for Heat-Shock Proteins 8.7.6 Genomic-Assisted Breeding 8.7.7 Transcriptome Analysis 8.7.8 MicroRNAs (miRNA) 8.8 Metabolite Changes 8.9 Genome Editing 8.10 Transgenics 8.11 Mutation Breeding 8.12 Next-Generation Platforms 8.13 Conclusion References 9: Current and Future Strategies in Breeding Lentil for Abiotic Stresses 9.1 Introduction 9.1.1 Nutritional Benefit and Their Health Significance 9.1.2 Effect of Stress on Quality and Crop Yield 9.1.3 Lentils in the Midst of Climate Change and Rising Population 9.2 Major Abiotic Stresses Influencing Lentil Productivity 9.2.1 Heat Stress 9.2.2 Cold Stress 9.2.3 Drought Stress 9.2.4 Submergence and Flooding Stress 9.2.5 Salinity Stress 9.3 Crop Wild Relatives (CWRs) of Lentil and Abiotic Stress 9.3.1 Molecular Genetic Diversity in Lentil 9.3.2 Next-Generation Technologies 9.3.3 Molecular Mapping of Resistance/Tolerance Genes and QTLs in Lentil 9.3.4 Abiotic Stresses and Transcriptome Analysis in Lentil 9.3.5 Marker-Assisted Selection (MAS) in Lentil Improvement 9.4 Conclusion References 10: Molecular and Physiological Approaches for Effective Management of Drought in Black Gram 10.1 Introduction 10.2 Different Mechanisms of Plants to Manage Drought Stress 10.2.1 Drought Escape 10.2.2 Drought Avoidance 10.2.3 Drought Tolerance 10.3 Drought Tolerance Mechanism in Legumes 10.4 Compatible Solute Accumulation 10.5 Antioxidant Defense 10.6 Hormone Regulation 10.7 Important Traits for Managing or Adopting Drought Stress in Black Gram 10.7.1 Root Morphology and Plasticity 10.7.2 Stomatal Conductance 10.7.3 Slow Canopy Wilting (SW) 10.7.4 Epidermal Conductance 10.7.5 Leaf Pubescence Density 10.7.6 Water-Use Efficiency 10.7.7 Osmotic Adjustment 10.8 Various Strategies of Drought Stress Management 10.8.1 Physiological Approach 10.8.1.1 Exogenous Application of Growth-Regulating Chemicals 10.8.1.2 Hydrogels 10.8.1.3 Application of Fertilizer 10.8.2 Molecular Approaches for the Development of DS-Tolerant Legumes 10.8.2.1 Breeding Approach 10.8.2.2 Quantitative Trait Loci (QTL) and Molecular Assisted Breeding 10.8.2.3 Transgenic Approach 10.8.2.4 Genome Editing (GE) by CRISPR/Cas9 10.9 Conclusions and Future Research Perspectives References 11: Abiotic Stress Responses in Groundnut (Arachis hypogaea L.): Mechanisms and Adaptations 11.1 Introduction 11.2 Abiotic Stress Responses in Groundnut 11.2.1 Morphological Responses 11.2.2 Reproductive Responses 11.2.3 Physiological Responses 11.2.4 Biochemical and Molecular Responses 11.3 Tolerance Mechanisms and Adaptation 11.3.1 Morphophysiological Mechanisms 11.3.2 Molecular Mechanisms 11.4 Strategies for Improving Abiotic Stress Tolerance 11.5 Conclusion References 12: Molecular Mechanisms of Nutrient Deficiency Stress Tolerance in Legumes 12.1 Introduction 12.2 Physiological Tolerance Mechanisms to Nutrient Deficiency in Legumes 12.3 Molecular Basis of Nutrient Uptake Under Starvation Conditions 12.3.1 Phosphorus 12.3.1.1 Uptake and Transport 12.3.1.2 Regulation of Pi Transporters 12.3.1.3 Regulation of Pi Transporters by Arbuscular Mycorrhizal Fungi 12.3.2 Potassium 12.3.2.1 K Uptake and Transport 12.3.2.2 Regulation of K Transporters 12.3.3 Sulphur 12.3.3.1 S Uptake and Transport 12.3.3.2 Regulation of S Transporter 12.3.4 Magnesium 12.3.4.1 Mg Uptake and Transport 12.3.5 Calcium 12.3.5.1 Ca Uptake and Transport 12.3.5.2 Regulation of Ca Transporters 12.3.6 Metal Divalent Cations: Fe, Zn, and Mn 12.3.6.1 Uptake, Transport, and Regulation of Metal Divalent Cations 12.4 Conclusions References 13: Stress Memory and Its Mitigation via Responses Through Physiological and Biochemical Traits in Mung Bean Under Moisture St... 13.1 Introduction 13.1.1 Drought Stress 13.1.2 Hormonal Profiling Reveals Stress Memory 13.1.3 Leaf Water Contents, Gas Exchange, and Chlorophyll Fluorescence 13.1.4 Photosynthetic Pigments and Antioxidants 13.1.5 Source-Sink Relationships 13.1.6 Biometric Traits 13.1.7 Biochemical Traits 13.1.8 Seedling Traits 13.2 Conclusion References 14: Genetic Engineering for Enhancing Abiotic Stress Tolerance in Pulses 14.1 Introduction 14.1.1 Drought 14.1.2 Salinity 14.1.3 Waterlogging 14.1.4 Temperature Extremities 14.2 Genetically Engineered Pulses for Abiotic Stress Tolerance 14.2.1 Chickpea 14.2.2 Pigeon Pea 14.2.3 Mung Bean 14.2.4 Urdbean 14.2.5 Cowpea 14.2.6 Field Pea 14.2.7 Common Bean 14.2.8 Lentil 14.3 Conclusions References 15: Aluminum Toxicity Tolerance in Food Legumes: Mechanisms, Screening, and Inheritance 15.1 Introduction 15.2 Genotypic Differences in Al Tolerance Among Legumes 15.3 Symptoms of Al Toxicity in Legumes 15.4 Physiological and Biochemical Mechanisms of Al Tolerance in Food Legumes 15.5 Physiological and Biochemical Parameters Associated with Al Tolerance in Legumes 15.5.1 Organic Acid Exudation 15.5.2 Callose Accumulation 15.5.3 Mucilage Secretion 15.5.4 Al-Induced Antioxidant Enzyme Production 15.5.5 Lipid Peroxidation 15.5.6 Nutritional Interaction 15.5.7 Visual Detection of Al Contents 15.6 Screening Techniques for Al Tolerance 15.6.1 Short-Term Screening Techniques 15.6.1.1 Hematoxylin Staining Method 15.6.1.2 Eriochrome Cyanine R Staining 15.6.1.3 Root Regrowth After Staining 15.6.1.4 Root Regrowth Without Staining 15.6.1.5 Fluorescence Staining Methods 15.6.1.6 Callose Deposition 15.6.1.7 Detection of Al-Induced H2O2 Level 15.6.2 Long-Term Screening Techniques 15.6.2.1 Nutrient Solution Culture Without Staining 15.6.2.2 Relative Root Length (RRL) 15.6.2.3 Root System Architecture 15.6.2.4 Sand Culture 15.6.2.5 Soil Culture 15.7 Genetics and Molecular Aspects of Al Tolerance in Legumes 15.8 Conclusion and Future Perspectives References This edited volume provides state-of–the-art overview of abiotic stress responses and tolerance mechanisms of different legume crops viz., chickpea, mung bean, lentil, black gram, cowpea, cluster bean, soybean and groundnut. Legumes play an important role in human nutrition and soil health through fixation of nitrogen. Legume production and productivity are vulnerable to different abiotic stresses. A proper understanding about the physiological and molecular basis of the legume crops is essential for genetic improvement of abiotic stress tolerance. This book consists of 15 chapters covering physiological and biochemical basis, molecular physiology, molecular breeding, genetics, genomics, transgenics, epigenetics of drought, saline, high temperature and nutrient deficiency stresses, and the role of microRNAs in abiotic stress tolerance. This volume offers new perspectives in legume crop abiotic stress management, and is useful for various stakeholders, including post graduates students, scientists, environmentalists and policymakers.