Biology of Earthworms (eBook)

Preface 6
Contents 10
Contributors 12
Chapter 1: Antimicrobial Vermipeptides: From Methods to Characteristics 16
1.1 Introduction 16
1.2 Protocol of Antibacterial Vermipeptide Preparation and Activity Assays 17
1.2.1 Animal and Bacterial Strains 17
1.2.2 Preparation of Crude Specimen 18
1.2.3 Purification of the Peptide 19
1.2.3.1 DE-52 Ion Exchange Chromatography 19
1.2.3.2 Gel Filtration 19
1.2.3.3 HPLC Purification of Peptide 19
1.2.4 Assessment of Peptide Characters 20
1.2.4.1 Molecular Weight Determination 20
1.2.4.2 Amino Acid Sequence Determination of the Isolated Peptide 20
1.2.4.3 Antibacterial Assays 20
1.2.4.4 Antitumor Activity Assays 20
1.2.4.5 Antiviral Activity Assays 21
1.3 Antibacterial Characteristics from Coelomic Fluid to Pure Peptide 21
1.3.1 Antibacterial Effects of Raw Coelomic Fluid of Earthworm 21
1.3.2 Antibacterial Effects of Earthworm Crude Antibacterial Peptides 22
1.3.3 Antibacterial Effects of Pure Antibacterial Peptides 22
1.3.4 Antimicrobial Chart of AVPF 23
1.3.5 Antitumor Activity of AVPF 23
1.3.6 Antiviral (PRV) Activity 25
1.4 Inducement of Peptides 25
1.4.1 Inducement Methods and Effects of Vermipeptide 25
1.4.1.1 Bacterial Treatment 25
1.4.1.2 Physical Treatment 26
1.4.1.3 Chemical Treatment 26
1.4.2 Characteristics of Induced Peptides 26
1.4.2.1 Antibacterial Vermipeptide Inducement 26
1.4.2.2 Spectrum of Fortypeptide 27
1.4.2.3 Evaluation of Different Inducements for Antimicrobial Peptides 27
1.4.2.4 Comparison of Antibacterial Components of Coelomic Fluid Extraction 28
1.5 Antibacterial Vermipeptide Family Found 29
1.6 Conclusion 31
References 31
Chapter 2: Optimizing Earthworm Sampling in Ecosystems 33
2.1 Introduction 33
2.2 How to Sample? Optimizing Earthworm Sampling Methods 34
2.2.1 Material and Methods 35
2.2.1.1 Preparation of Expellants 35
2.2.1.2 Earthworm Sampling 36
2.2.2 Salient Observations 37
2.2.2.1 Concentration Optimization 37
2.2.2.2 Efficiency Assessment 38
2.2.3 Interpretation 40
2.2.3.1 Concentration Optimization 40
2.2.3.2 Efficiency Assessment 41
2.3 Where to Sample? Optimizing Spatial Sampling Design 43
2.3.1 Spatial Autocorrelation and Sampling Design 43
2.3.2 Sample Unit Size and Shape 44
2.4 How Many Samples? Optimizing Sample Size 47
2.5 Conclusion 50
References 50
Chapter 3: Earthworms and Soil Structure 53
3.1 Introduction 53
3.2 Soil Aggregates and Structure 53
3.3 Earthworms and Soil Structure 55
3.3.1 Earthworm Species Effects on Burrowing and Casting 57
3.3.2 The Effect of Burrows on Soil Structure 58
3.3.3 The Effect of Casts on Soil Structure 59
3.4 Conclusion 61
References 61
Chapter 4: Comparative Anatomy of the Calciferous Gland of Lumbricid Earthworms 65
4.1 Introduction 65
4.2 Materials and Methods 67
4.3 Calciferous Gland Types Based on Anatomy 67
4.3.1 Well Developed Esophageal Pouches in Segment X and Lateral Enlargements in Segments XI and XII (Subtype I: Anterior and Posterior Lateral Enlargements of Similar Size) 67
4.3.2 Well-Developed Esophageal Pouches in Segment X and Lateral Enlargements in Segments XI and XII (Subtype II: Glandular Portion in Segment XII Smaller in Size) 70
4.3.3 Small Esophageal Pouches in Segment X and Lateral Enlargements (Subtype I: Glandular Portion in Segment XI Bigger in Size) 71
4.3.4 Small Esophageal Pouches in X and Lateral Enlargements (Subtype II: Variable Number of Dilated Segments) 72
4.3.5 Well-Developed Esophageal Pouches in X But No Lateral Enlargements 73
4.3.6 Esophageal Pouches in X Absent But Lateral Enlargements Present in Segments XI and XII (Subtype I: Segment X Not Enlarged) 76
4.3.7 Esophageal Pouches in X Absent But Lateral Enlargements Present in Segments XI and XII (Subtype I: Segment X Dilated) 77
4.4 Conclusions 79
References 79
Chapter 5: Reproduction of Earthworms: Sexual Selection and Parthenogenesis 82
5.1 Introduction 82
5.2 Sexual Selection in Cross-Fertilization Earthworms 84
5.2.1 Precopulatory Sexual Selection 84
5.2.2 Postcopulatory Sexual Selection 86
5.3 Parthenogenesis 89
5.3.1 Definition 89
5.3.2 Types of Parthenogenesis in Earthworms 89
5.3.3 Parthenogenesis and Polyploidy 92
5.3.4 Genetic and Ecological Consequences of Cloning 92
5.3.5 The Species Concept in Parthenogenetic Earthworms 93
5.3.6 The Origin of Parthenogenetic Forms 95
5.4 Conclusion 96
References 96
Chapter 6: The Earthworm Inoculation Unit Technique: Development and Use in Soil Improvement Over Two Decades 100
6.1 Introduction 100
6.2 Earthworms as Ecological Engineers 100
6.3 Established Inoculation Techniques 104
6.4 Development of the EIU Technique: From Tea Chests to Plastic Bags 105
6.5 First Trial: Calvert 1991 106
6.6 Down Sizing and Mixed Cultures 107
6.7 An Industrial Application: In Scotland and Poland 110
6.8 An Agricultural Trial: In the USA and in Finland 112
6.9 A French Connection 114
6.10 Bearing Fruit in New Zealand 114
6.11 Future Developments of the EIU Technique 114
References 116
Chapter 7: Controlled Cultivation of Endogeic and Anecic Earthworms 119
7.1 Introduction 119
7.2 Earthworm Ecological Groupings 119
7.3 Controlled Earthworm Cultivation 121
7.4 Why Cultivate Endogeic and Anecic Species? 125
7.4.1 Life History Studies, Species Interactions and Population Ecology 125
7.4.2 Ecosystem Improvement 127
7.4.3 Ecotoxicology 129
7.5 A Future for Cultivation of Soil Dwelling Earthworms 131
References 131
Chapter 8: The Meek Shall Inherit the Burrow: Feedback in Earthworm Soil Modification 134
8.1 Introduction 134
8.2 Earthworm Soil Modification: A Soil Improvement Adaptation? 136
8.2.1 Viewpoints of Earthworm Adaptations 136
8.2.2 Niche Construction and Ecological Inheritance Perspectives 139
8.3 A Case of Ecological Inheritance in the Dew Worm 141
8.3.1 Dew Worm Life Style 141
8.3.2 Indications of Burrow and Living Site Inheritance 142
8.3.3 Implications 145
8.4 Conclusion 147
References 149
Chapter 9: Earthworm Interactions with Soil Enzymes 152
9.1 Introduction 152
9.2 Soil Earthworms 153
9.3 Soil Enzymes 154
9.4 Relationships Between Soil Earthworms and Enzymes 155
9.4.1 Interactions in Microscale 155
9.4.2 Interactions in Mesoscale 157
9.4.3 Interactions in Macroscale 159
9.4.4 Effects of Agricultural Activities on Earthworm-Enzyme Interactions 159
9.5 Conclusion 163
References 164
Chapter 10: The Impact of Cultivation Techniques on Earthworm Populations 170
10.1 Introduction 170
10.2 The Effects of Cultivation and Cropping on Earthworms 171
10.3 Earthworm Populations in Cultivated Soil 172
10.3.1 The Effect of Crop Rotations on Earthworm Populations 178
10.3.2 The Effect of Crop Residue Disposal on Earthworm Populations 179
10.4 Conclusion 180
References 181
Chapter 11: Assessing the Role of Earthworms in Biocontrol of Soil-Borne Plant Fungal Diseases 184
11.1 Introduction 184
11.2 Soil-Borne Plant Fungal Diseases 186
11.3 Biocontrol of Soil-Borne Fungal Diseases 187
11.4 Mechanisms of Soil-Borne Fungal Disease Suppression Due to Earthworm Activity 188
11.4.1 Changes in Microbial Community Dynamics 188
11.4.2 Enzymatic Activity 190
11.4.3 Production of Antifungal Compounds 191
11.4.3.1 Antibiotics 191
11.4.3.2 Phenolics 191
11.4.3.3 Antimicrobial Peptides 192
11.4.4 Physicochemical Properties of Soil 193
11.4.5 Induced Systemic Resistance in Plants 194
11.5 Conclusion 195
References 196
Chapter 12: The Use of Vermicompost Products to Control Plant Diseases and Pests 201
12.1 Introduction 201
12.2 The Use of Vermicompost Products for Plant Disease and Pest Control 202
12.2.1 Application of Solid Vermicomposts for Plant Disease Control 202
12.2.2 Application of Solid Vermicomposts for Plant Pest Control 206
12.2.2.1 Suppression of Plant Arthropod Pests 207
12.2.2.2 Suppression of Plant Parasitic Nematodes 209
12.3 Application of Vermicompost Extracts for Plant Disease and Pest Control 210
12.3.1 Application of Vermicompost Extracts for Plant Disease Control 210
12.3.2 Application of Vermicompost Extracts for Plant Pest Control 212
12.3.2.1 Suppression of Plant Arthropod Pests 213
12.3.2.2 Suppression of Plant Parasitic Nematodes 213
12.4 Mechanisms of Plant Disease Suppression by Vermicompost Products 214
12.5 Mechanisms of Plant Pest Control by Vermicompost Products 216
12.6 Important Factors of Disease Suppression Mechanisms by Vermicompost Products 217
12.7 Conclusions 219
References 220
Chapter 13: Vermicompost as a Biological Soil Amendment 224
13.1 Introduction 224
13.2 Characteristics of Vermicompost 225
13.3 Potential Application of Earthworms and Vermicompost in Plant Growth 226
13.4 Metals and Agrochemicals Accumulation from Soil by Earthworms 227
13.5 Plant Growth Trials Using Vermicomposts 227
13.6 Disease and Pest Suppression 228
13.7 Accumulation of Heavy Metals 229
13.8 Potential for Transmission of Pathogens 230
13.9 Effect of Worm Castings on Crop Yields 230
13.10 Detrimental Effects of Earthworms 231
13.11 Interpretation of Findings 232
13.12 Conclusion 232
References 234
Chapter 14: Earthworm Innate Immune System 238
14.1 Introduction 238
14.2 Innate Immune Recognition in Earthworms 239
14.3 Coelomocyte Proliferation After Depletion and Mitogen Stimulation 239
14.4 Earthworm Coelomocytes Are Positive for Different Mammalian Antigen-Specific Monoclonal Antibodies 241
14.4.1 Molecules with Cytokine-Like Activity 241
14.4.2 FACS Reveals Distinct Coelomocyte Subtypes Based on CD Marker Properties 241
14.5 Earthworm Leukocytes Deploy Lysosomal Enzymes That Respond to Bacterial Challenge 242
14.6 Specific Monoclonal Antibodies Identify Four Distinct Earthworm Coelomocyte Markers 244
14.6.1 Establishing a CD Marker Library 244
14.6.2 Characterization of Coelomocyte Differentiation Clusters 245
14.7 Signaling Mechanisms by Mitogen-Activated Protein Kinases in Invertebrate Immunocytes 246
14.7.1 Signaling a Common and Important Mechanism 246
14.7.2 The Essential Role of Phosphorylation to Activate MAPKs 248
14.8 Is MAPK Pathway Involved in Earthworm Immune Response? 248
14.9 Conclusions and Future Prospects 249
References 250
Chapter 15: Earthworms: A Potent Herbal Target for TCM (CAM) Research 255
15.1 Introduction 255
15.2 Peripheral Nerve Regeneration 256
15.2.1 MAPK Pathway: Stimulating Schwann Cells Migration 258
15.2.2 IGF-I Pathway: Stimulating Schwann Cells Proliferation 258
15.2.3 PACAP-Like Compound 259
15.2.4 G-90 259
15.2.5 Optimal Dosage of Earthworm Extract 259
15.3 Pharmacological and Clinical Application 260
15.3.1 Fibrinolytic Enzyme 260
15.3.2 G-90 Glycolipoprotein 263
15.3.3 Polyphenolic 263
15.4 The Impacts on Ecological Systems 264
15.5 The Challenges After Breaking the Balance of Ecological Systems 264
15.6 Conclusion and Perspectives 264
References 266
Chapter 16: Earthworms as Bioindicators of Soil Quality 269
16.1 Introduction: Soil Quality and Soil Health 269
16.2 Monitoring of Earthworm Communities 270
16.2.1 Monitoring Programs 270
16.2.2 Monitoring Results 273
16.2.3 Indicator Values of Earthworm Species Derived from Their Habitat Requirements 273
16.2.4 Constraints on the Interpretation of Earthworm Abundance as an Indicator of Soil Quality 273
16.3 Bioindication with Earthworms in Laboratory Assays 275
16.3.1 Avoidance Test 275
16.3.1.1 Two-dimensional terraria 276
16.4 Monitoring of Earthworms as Accumulators of Metals and Xenobiotica 277
16.4.1 Suitability of Earthworms as Accumulation Indicators 277
16.4.2 What Chemicals/Elements Have Been Found to Accumulate? 278
16.4.3 What Influences the Uptake of Chemicals by Earthworms? 279
16.4.4 What is the Use of Taking Earthworms as Accumulation Indicators of Environmental Chemicals? 281
16.5 Conclusion 281
References 282
Chapter 17: Application of Molecular Genetics to Earthworm Ecology: Current Research and Promising Future Directions 287
17.1 Introduction 287
17.2 Current Molecular Markers for Earthworm Genetics 288
17.2.1 mtDNA Markers 289
17.2.2 Microsatellites 292
17.2.3 AFLPs 294
17.3 Inferring Mating Strategies from Molecular Data in Amphimictic Earthworms 294
17.3.1 Selfing and Inbreeding 295
17.3.2 Multiple Mating 295
17.3.3 Post-Copulatory Sexual Selection 296
17.3.4 Genetic Compatibility and Mate Choice 297
17.4 Determining Patterns of Earthworm´s Dispersal Using Molecular Data 298
17.4.1 What Is a `Population´ for Earthworms? 299
17.4.2 Modes and Pathways of Earthworms Dispersal 299
17.4.3 Invasion by Earthworms 300
17.5 Conclusion 301
References 301
Chapter 18: Population Dynamics of Earthworms in Organic Farming Systems 306
18.1 Introduction 306
18.2 Earthworm Life Cycle 307
18.3 Long-Term Effects of Farming Systems on Population Dynamics 309
18.4 Methodological Limitations 310
18.5 Earthworm Population Dynamics at the WVU Organic Research Farm 311
18.5.1 Low-Input Treatment 312
18.5.2 High-Input Treatment 312
18.5.3 Observations 313
18.6 Conclusion 315
References 316
Index 318