The Rhizosphere

ISBN-13: 9783642707247 / Angielski / Miękka / 2011 / 288 str.

Elroy A. Curl; Bryan Truelove

Opis

The Plant Root and the Rhizosphere was a major topical feature of the first International Symposium on Factors Determining the Behavior of Plant Pathogens in Soil held at the University of California, Berkeley in 1963. The symposium was edited by K. F. Baker and W. C. Snyder and published under the title Ecology of Soil-Borne Plant Pathogens. Since that time, several other international efforts, either on the root-soil interface specifically or on topics relating to the root environment, have provided"a wealth of valuable information basic to promoting the culture of healthier, more productive plants. For the writing of this book, inspiration has come, in large part, from 10 years of cooperative rhizosphere research in association with leading scientists participating in a regional effort within the southern United States. We have attempted to bring together in this work the major aspects of rhizosphere research and the principles of rhizosphere ecology for the benefit of developing young scientists and technologists, as well as for the established professional researcher and teacher. A prime objective and hope is that this volume might generate ideas that will bring forth new approaches and methodology leading to further advances in our understanding of rhizosphere interactions and their implications for agriculture. ' Because of the enormous complexity of the chemical, physical, and microbiological environment of roots, the methods used by various workers are rarely standardized, but must be devised or modified for each experiment.

Spis treści

1 Introduction.- 1.1 Definitions and Historical.- 1.2 The Root Environment.- 1.3 Significance and Purpose of Rhizosphere Investigations.- 2 The Structure and Function of Roots.- 2.1 Introduction.- 2.2 Root Morphology.- 2.3 Root Structure.- 2.3.1 Organization of the Apical Region.- 2.3.2 The Subapical Region of the Root.- 2.3.3 The Tissues of the Root.- 2.3.4 Lateral Root Formation.- 2.3.5 Secondary Growth of Roots.- 2.4 Root Physiology.- 2.4.1 Plants and Water.- 2.4.2 Plant Cell-Water Relations.- 2.4.3 Movement of Water Through the Plant.- 2.4.4 Movement of Water from Soil to the Root Xylem.- 2.5 The Root-Soil Boundary.- 2.6 Root Exudation.- 3 Root Exudates.- 3.1 Introduction.- 3.2 Methods of Collection and Analysis.- 3.3 Qualitative and Quantitative Nature of Exudates.- 3.3.1 Carbohydrates and Amino Acids.- 3.3.2 Organic Acids and Lipids.- 3.3.3 Growth Factors.- 3.3.4 Enzymes.- 3.3.5 Miscellaneous Compounds.- 3.4 Sites of Exudate Release.- 3.5 Factors Affecting Exudation.- 3.5.1 Plant Species and Developmental Stage.- 3.5.2 Temperature and Light.- 3.5.3 Soil Moisture and Atmosphere.- 3.5.4 Plant Nutrition.- 3.5.5 Plant-Injury Factors.- 3.5.6 Microbial Effects.- 3.5.7 Foliar Sprays.- 3.6 Sloughed Organic Matter.- 4 Rhizosphere Populations.- 4.1 Introduction.- 4.2 Isolation and Enumeration of Microorganisms.- 4.2.1 The Microflora.- 4.2.2 The Fauna.- 4.3 Populations of the Microflora.- 4.3.1 Bacteria.- 4.3.2 Actinomycetes.- 4.3.3 Fungi.- 4.3.4 Algae.- 4.4 Qualitative Changes in the Microflora.- 4.4.1 The Bacterial Flora.- 4.4.2 The Fungal Flora.- 4.5 Factors Affecting Populations of the Microflora.- 4.5.1 Plant Type, Developmental Stage, and Vigor.- 4.5.2 Soil Type.- 4.5.3 Soil Treatment.- 4.5.4 Foliar Treatments.- 4.5.5 Environmental Factors.- 4.5.6 Microbial Interrelationships.- 4.6 Populations of the Rhizosphere Fauna.- 4.6.1 Protozoa.- 4.6.2 Nematodes.- 4.6.3 The Acari and Collembola.- 5 Microbial Interactions.- 5.1 Introduction.- 5.2 Growth-Promoting Interactions.- 5.2.1 Commensalistic Relationships.- 5.2.2 Mutualistic Relationships.- 5.3 Growth-Inhibiting Relationships (Antagonism).- 5.3.1 Competition in the Rhizosphere.- 5.3.2 Antibiosis and Microbial Stasis.- 5.3.3 Parasitism and Predation.- 6 Rhizosphere in Relation to Plant Nutrition and Growth.- 6.1 Introduction.- 6.2 Nutrient Availability and Uptake.- 6.2.1 Mineralization from Organic Sources.- 6.2.2 Phosphate Availability and Absorption by Plants.- 6.2.3 Availability and Uptake of Other Elements.- 6.2.4 Microorganism Effects on Root Morphology.- 6.2.5 Fauna Influence on Nutrient Uptake.- 6.3 Nonsymbiotic Nitrogen Fixation.- 6.4 Symbiotic Relationships.- 6.4.1 Legume-Rhizobium Interactions.- 6.4.2 Rhizosphere Effect on Mycorrhizae.- 6.5 Microbial Metabolites.- 6.5.1 Growth-Promoting Factors.- 6.5.2 Growth Inhibition.- 6.6 Plant Effects on Other Plants.- 6.6.1 Growth Stimulation.- 6.6.2 Allelopathy.- 7 Rhizosphere Relation to Plant Disease.- 7.1 Introduction.- 7.1.1 General Ecology.- 7.1.2 Inoculum Potential.- 7.2 Pathogen Populations.- 7.2.1 Bacteria and Fungi.- 7.2.2 Nematode Populations.- 7.3 Growth and Survival in the Rhizosphere.- 7.3.1 Bacteria.- 7.3.2 Host-Dependent Fungal Pathogens.- 7.3.3 Fungal Pathogens with High Saprophytic Ability.- 7.4 Pathogenesis.- 7.4.1 Fungal Pathogens.- 7.4.2 Nematode Activity.- 7.4.3 Rhizosphere Factors Influencing Disease Resistance.- 7.5 Pathogenesis Without Parasitism.- 7.6 Disease Control.- 7.6.1 Use of Pesticides.- 7.6.2 Biological Control of Bacterial and Fungal Pathogens.- 7.6.3 Role of the Microflora in Nematode Control.- 7.6.4 Role of the Soil Fauna in Biological Control.- 7.6.5 Host Resistance.- 8 Current Trends and Projected Emphasis.- 8.1 General Overview.- 8.2 Status of the Technology.- 8.3 Relating to Plant Growth.- 8.3.1 Challenge of Symbiosis.- 8.3.2 Interactions in Symbiosis.- 8.3.3 Nonsymbiotic Activities Reexamined.- 8.3.4 The Root-Shoot Relationship.- 8.4 Opportunities in Plant Pathology.- 8.4.1 Modeling the Rhizosphere.- 8.4.2 New Challenges in Biological Control.- 8.5 Focus: The Rhizosphere and Crop Production.- References.