Diversity and Biotechnology of Ectomycorrhizae (eBook)

Preface 8
Contents 10
Contributors 14
Part I: Diversity, Morphology and Applications 18
Chapter 1: The Importance of Ectomycorrhizas for the Growth of Dipterocarps and the Efficacy of Ectomycorrhizal Inoculation Schemes 19
1.1 Introduction 19
1.2 Fungal Species Associated with Dipterocarps 20
1.3 Nutrient Relationships 20
1.4 Inoculation Experiments 21
1.4.1 Inoculation with Single Species 22
1.4.1.1 Malaysian Inoculation Experiments 22
1.4.1.2 Indonesian Inoculation Experiments 23
1.4.2 Other Inoculation Methods 24
1.4.2.1 Mycorrhizal Tablets 24
1.4.2.2 Mother Tree Inoculation 24
1.4.3 Production of Inoculum 24
1.4.4 Field Experiments 25
1.5 Under What Conditions Will EcM Inoculation Be Beneficial? 26
1.5.1 Successful Inoculation Schemes 27
1.5.2 When and Where to Inoculate? 27
1.6 Conclusions 28
References 28
Chapter 2: The Ectomycorrhizal Symbiosis in South America: Morphology, Colonization, and Diversity 34
2.1 Introduction 34
2.2 ECM Studies in South America 35
2.3 Morphological and Anatomical Features of the ECM in South America 40
2.4 Conclusion 50
References 50
Chapter 3: Ectomycorrhizal Inoculum and Inoculation Techniques 57
3.1 Introduction 57
3.2 Isolation and Manipulation of Fungal Pure Cultures, Nutrient Media 58
3.3 Synthesis of Ectomycorrhizae in Controlled Conditions 59
3.3.1 Fungal Cultures Preparation 59
3.3.2 Inoculation Techniques 60
3.3.2.1 Sterile Techniques 60
Petri Dishes 60
Flasks and Jars 61
Test Tubes 61
Polycarbonate Boxes 62
3.3.2.2 Semi- and Non-sterile Techniques 62
Growth Pouches 62
Pots, Containers, Vessels 63
3.4 Greenhouse and Nursery Inoculation 64
3.4.1 Inoculum Types 64
3.4.1.1 Natural Inoculum (Soil, Humus, Ectomycorrhizae) 64
3.4.1.2 Basidiospores 64
3.4.1.3 Vegetative (Mycelial) Inoculum 65
Mycelial Suspension (Slurry) 65
Vermiculite-Peat (Substrate Carrier) Inoculum 66
Alginate-Bead Inoculum 66
3.4.2 Methods of Inoculum Application 67
3.4.2.1 Basidiospores 67
3.4.2.2 Natural and Vegetative Inoculum 69
3.5 Field Inoculation 70
3.6 Commercial Inoculum 71
3.7 Conclusion 72
References 72
Part II: Biotechnological Aspect of ECM 78
Chapter 4: Systematics and Ecology of Tropical Ectomycorrhizal Fungi Using Molecular Approaches 79
4.1 Evaluation of Tropical ECM Species Composition 79
4.1.1 Introduction 79
4.1.2 ECM Systematics and Diversity Assessment 81
4.1.2.1 ECM Status of Tropical Trees 82
4.1.2.2 Ectomycorrhizas Diversity 82
4.2 Genet Distribution of Russula sp. foetentinae in a Tropical Rainforest 87
4.2.1 Introduction 87
4.2.2 Methods 89
4.2.2.1 Spatial Randomness 89
4.2.2.2 Genotype Identification 89
4.2.3 Discussion 90
4.3 Conclusion 93
References 93
Chapter 5: The Molecular Ectomycorrhizal Fungus Essence in Association: A Review of Differentially Expressed Fungal Genes During Symbiosis Formation 98
5.1 Introduction 98
5.2 Ectomycorrhizal Genes Differentially Expressed During Symbiosis Formation 99
5.2.1 Growth and Cell Organization Genes 99
5.2.2 Morphogenesis 103
5.2.3 Energy and Metabolism 103
5.2.3.1 Carbohydrate Metabolism 103
5.2.3.2 Lipid Metabolism 110
5.2.3.3 Amino Acid and Protein Metabolism 110
5.2.3.4 Nucleic Acids Metabolism 111
5.2.4 Protein Synthesis and Interaction, Transcriptional and Translational Regulation 111
5.2.5 Ions, Amino Acids and Peptides Transports 111
5.2.6 Signaling and Structural Membrane Proteins 120
5.2.7 DNA/RNA Processing 120
5.2.8 Cell Defense and Apoptosis 123
5.3 Conclusions 127
References 128
Chapter 6: Agrobacterium tumefaciens-Mediated Transformation of Ectomycorrhizal Fungi 133
6.1 Introduction 133
6.2 Genetic Modification of ECM Fungi with Traditional Transformation Methods 134
6.3 Agrobacterium-Mediated Transformation of Fungi 135
6.4 AMT of ECM Fungi 136
6.5 AMT-Mechanisms: T-DNA Transfer to the Host Cell 137
6.5.1 Pretransfer Bacterial Processes Leading to T-DNA Mobilization 138
6.5.2 T-Strand Transfer 138
6.5.3 Host Cell Events Leading to T-DNA Integration in the Host Genome 139
6.6 Molecular Mechanism of AMT in Fungi 140
6.7 Use of AMT in Fungal Genetics 141
6.8 AMT-Mediated Random Gene Tagging 141
6.9 Is Random T-DNA Tagging of Fungal Genome Really at Random? 142
6.10 Targeted Gene Disruption by AMT 143
6.11 Laccaria bicolor Represents a Special Challenge for AMT as a Reverse Genetic Tool 144
6.12 Conclusion 146
References 146
Chapter 7: Biotechnological Processes Used in Controlled Ectomycorrhizal Practices 152
7.1 Introduction 152
7.2 Criteria to Adopt an Inoculum Formulation 154
7.3 Spore-Based Fungal Inoculum 154
7.3.1 Formulation of Spore Inoculums and Effect on Plant Growth 154
7.4 Mycelium-Based Fungal Inoculums 155
7.4.1 Fungal Isolation from Fruit Bodies 155
7.4.2 Formulation of Mycelium-Based Inoculums and Effect on Plant Growth 157
7.4.2.1 Vermiculite-Peat Inoculums (Marx and Bryan 1975) 157
7.4.2.2 Encapsulation of Hyphal Fragments Within Beads of Alginate Gel (Mauperin et al. 1987) 158
7.4.2.3 Controlled Ectomycorrhization in Glasshouse, Nursery, and Field Conditions 159
Screening for Efficient Fungal Isolates in Controlled Conditions 159
Controlled Inoculation in Field Conditions 159
7.5 Conclusion 161
References 161
Chapter 8: Signaling in Ectomycorrhizal Symbiosis Establishment 165
8.1 Introduction 165
8.2 Ectomycorrhiza Formation 166
8.3 Rhizospheric Signals Emitted During the Preinfection 167
8.4 Proteins Involved in Fungal Attachment to the Root Host Surface and Formation of Symbiotic Interface 171
8.5 Ectomycorrhizal Morphogenesis 174
8.6 Induction of Plant Defense Responses by Ectomycorrhizal Fungi 176
8.7 Conclusions 178
References 178
Chapter 9: RNA Silencing in Ectomycorrhizal Fungi 184
9.1 Introduction 184
9.2 RNAi Mechanisms 185
9.3 siRNA-Dependent RNA Silencing 186
9.3.1 siRNAs 186
9.3.2 Sources of dsRNA in Cells 187
9.3.3 Cytosolic siRNA-Mediated PTGS 187
9.4 miRNA-Mediated Translational Arrest 188
9.5 RdRP Amplification of the Silencing Trigger 189
9.6 siRISC Can Operate on Target mRNAs in Nuclear Environment Also 191
9.7 Epigenetic Effects Associated with RNAi 191
9.8 Use of RNAi as a Genetic Tool 192
9.9 RNA Silencing in Fungi 196
9.10 RNA Silencing Protein Machinery in Fungi 196
9.11 Viral Origin of RNAi in Fungi 197
9.12 RNA Silencing in Different Fungi 198
9.13 How RNAi Is Experimentally Initiated in Fungi 199
9.14 Simultaneous Silencing of Genes with a Single Trigger in Fungi 200
9.15 Use of RNAi as a Reverse Genetic Tool in Fungi 203
9.16 Gene Silencing in Ectomycorrhizal Fungi 203
9.17 Conclusion 207
References 207
Part III: Functions and Interactions 214
Chapter 10: Ectomycoremediation: An Eco-Friendly Technique for the Remediation of Polluted Sites 215
10.1 Introduction 215
10.2 Phytoremediation: An Alternative Method for the Remediation of Contaminated Sites 216
10.3 Ectomycorrhizal Associations and Their Significance for Phytoremediation 217
10.3.1 The Contribution of Rhizosphere and Ectomycorrhizosphere to Bioremediation 219
10.3.2 Ectomycoremediation of Organic Xenobiotics 222
10.3.2.1 Petroleum Hydrocarbons 223
10.3.2.2 Polycyclic Aromatic Hydrocarbons 224
10.3.2.3 Nitro-aromatics 226
10.3.2.4 Chlorinated Aromatic Hydrocarbons 226
10.3.3 Ectomycoremediation of Heavy Metals 227
10.4 Conclusions 229
References 230
Chapter 11: Metal Elements and the Diversity and Function of Ectomycorrhizal Communities 236
11.1 Introduction 236
11.2 Metal Element Cycling in ECM Forests 237
11.2.1 Biogeochemical Transformations of Metals in ECM Forest Soil 237
11.2.2 Weathering and Mineralization 237
11.2.3 Litter Decomposition 238
11.2.4 Metal Element Cycling and Translocation by ECMF 239
11.2.5 Relevance of Fungal Soil Metal Transformations 240
11.3 Metal Tolerance of ECM Associations 241
11.3.1 Metal Toxicity 241
11.3.2 Mechanisms of Metal Tolerance in ECMF 242
11.3.3 Protection of Host Trees 244
11.3.4 Are ECMF More Resistant to Toxic Metals Than Their Host Trees? 244
11.3.5 Can Metal-Resistant ECMF Confer Resistance to Their Host Trees? 244
11.3.6 ECMF and Host Tree Nutrient Status and Metal Uptake 245
11.3.7 Can ECM Symbiosis Confer Resistance to Sensitive Host Tree Genotypes? 246
11.4 Population Genetics of Adaptive Metal Tolerance in ECMF 246
11.5 Distribution of Metal Elements in ECMF 248
11.6 Transfer of Trace Metals to Vertebrate Food Webs via ECMF 250
11.7 Diversity and Structure of ECM Communities Exposed to Metal Toxicity 251
11.8 Biodiversity and Conservation 252
11.9 Conclusions 253
References 254
Chapter 12: A Conceptual Framework for Up-Scaling Ecological Processes and Application to Ectomycorrhizal Fungi 260
12.1 Introduction 260
12.2 Addressing the Up-Scaling Problem 261
12.3 An Analytic Conceptual Framework for Integration Across Scales 264
12.3.1 Developmental System as the Basic Unit of Ecological Functioning 264
12.3.2 Epistemic Status of the Developmental Systems 265
12.3.3 Scale and Productivity 266
12.3.4 Epistemic Status of Complex Ecological Systems 267
12.3.5 Up-Scaling the Ecological Processes 273
12.4 Application to Ectomycorrhizae 274
12.4.1 Scales Relevant for EMF Developmental Systems 275
12.4.1.1 Structural Issues 275
Dimension and Turnover Rate of EMFs 275
ST Location of EM Fungi 278
Resources for Ectomycorrhizal Fungi and Their Space-Time Location 281
Organisms Using Resources and Services Provided by EMF 282
External Control Factors 283
The Homomorphic Model for Up-Scaling 284
12.4.1.2 Functional Issues 285
Stratification 285
Scale-Specific Mechanisms of EMF Productivity 285
12.5 Disturbance and Succession of Ectomycorrhizal Systems 289
12.5.1 Role of EMF in the Functioning of the Natural Capital 291
12.5.2 Mathematical Modeling 293
12.6 Research Directions 293
12.7 Conclusions 296
References 296
Chapter 13: Mycobioindication of Stress in Forest Ecosystems 305
13.1 Introduction 305
13.2 Impact of Stress Factors on Mycorrhiza 306
13.2.1 Acid Deposition 306
13.2.2 Nitrogen Deposition and Fertilization 306
13.2.3 Metal Deposition 307
13.2.4 Ozone 308
13.2.5 Elevated CO2 309
13.2.6 Drought 309
13.3 Mycobioindication in Forest Ecosystems 310
13.3.1 Ecological Indicators and Passive Monitors of Stress in a Forest Ecosystem 313
13.3.1.1 Responsive In Situ Mycoindicators 313
13.3.1.2 Accumulative In Situ Passive Monitors 316
13.3.1.3 Conclusions on Indicators and Passive Monitors 317
13.3.2 Active Monitors of Stress in Forest Ecosystems 318
13.3.2.1 Active monitors: In Situ Exposed Nonmycorrhizal Seedlings 318
13.3.2.2 Ex Situ Testers: Mycorrhizal Inoculum Potential of Differently Polluted Soil Substrates 318
13.3.2.3 Conclusions on Active Indicators in Mycoindication 320
13.4 Final remarks 320
References 321
Chapter 14: Effects of Pesticides on the Growth of Ectomycorrhizal Fungi and Ectomycorrhiza Formation 327
14.1 Introduction 327
14.2 Forest Tree Mycorrhization 328
14.2.1 Controlled Mycorrhization 328
14.3 Pesticides 329
14.3.1 Classification of Pesticides 330
14.3.2 Effects of Pesticides on Soil Microorganisms 330
14.3.3 Pesticide Persistence in the Soil 331
14.4 Pesticides and EMF 333
14.4.1 Fungicides 338
14.4.2 Herbicides 339
14.4.3 Insecticides and Other Pesticides 341
14.5 Pesticides and Lactarius spp. 341
14.5.1 Fungicides 341
14.5.2 Herbicides 344
14.6 Conclusions 344
References 345
Chapter 15: Metal-Chelating Agents from Ectomycorrhizal Fungi and Their Biotechnological Potential 351
15.1 Introduction 351
15.2 Specific Metal-Chelating Agents: Siderophores 352
15.3 Non-specific Metal-Chelating Agents: Low Molecular Weight Organic Acids 359
15.4 Other Metal-Chelating Agents: Thiol-Peptides 363
15.5 Biotechnological Potential of ECM Fungi Producing Metal-Chelating Agents 365
15.6 Conclusions 367
References 368
Chapter 16: Ectomycorrhiza and Secondary Metabolites 374
16.1 Introduction 374
16.2 Flavonoids 377
16.3 Terpenes 378
16.4 Plant Growth Regulating Substances (phytohormones) 379
16.4.1 Auxins 380
16.4.2 Cytokinins 381
16.4.3 Gibberellins (GAs) 382
16.4.4 Ethylene 383
16.4.5 Abscisic Acid 383
16.5 Sterols 383
16.6 Conclusions and Future Perspectives 384
References 385
Chapter 17: C:N Interactions and the Cost:Benefit Balance in Ectomycorrhizae 389
17.1 Introduction 389
17.2 Nitrogen 390
17.2.1 N Assimilation, Transport, and Transference to the Plant 392
17.3 Carbon 393
17.3.1 C Transfer and Use by the Fungus 394
17.4 C-N Interactions 394
17.5 Cost/Benefit and the Symbiotic Continuum 396
17.6 Conclusions 400
References 400
Chapter 18: Ectomycorrhizal Interaction Between Cantharellus and Dendrocalamus 406
18.1 Introduction 406
18.2 Ectomycorrhiza Formation and Growth Response on Host Plant 408
18.2.1 Growth in Culture 408
18.2.2 Simplified Technique of Ectomycorrhizal Synthesis 408
18.2.3 Ectomycorrhizal Interaction 411
18.2.4 Mass Multiplication of Inoculum 413
18.2.5 Growth Response of Host Seedlings 415
18.3 Ecological Studies 416
18.3.1 General Ecology 416
18.3.2 Antagonistic Interactions with Rhizosphere Fungi 417
18.3.3 Acid Phosphatase Production 419
18.3.4 Activity of Acid Phosphatase 421
18.4 Conclusion 422
References 424
Chapter 19: Edible Ectomycorrhizal Fungi: Cultivation, Conservation and Challenges 430
19.1 Introduction 430
19.2 Occurrence 431
19.3 Role of Ectomycorrhizas 432
19.4 Mycorrhizal Mushrooms 432
19.5 Production and Forest Management 435
19.5.1 Ectomycorrhizal Mushrooms and Wildlife Association 436
19.6 Cultivation of Edible Mycorrhizal Mushrooms 436
19.6.1 Truffles 437
19.6.2 Russula 438
19.6.3 Cantharellus 439
19.6.4 Boletus 439
19.6.5 Cultivation of Other Species 440
19.7 Conservation 441
19.7.1 Challenges Ahead 442
19.8 Conclusions 443
References 444
Index 455