Biocommunication in Soil Microorganisms pp 215-235 | Cite as
Phage Biopesticides and Soil Bacteria: Multilayered and Complex Interactions
Abstract
Soil ecosystems are impacted by the application of biological control agents to aerial portions of plants. The use of bacteriophages, “phages,” as agriculture biopesticides has been adopted and utilized in a number of host–pathogen systems. Phages may be applied as aerial sprays, preplant treatments and soil drenches in concentrations up to 108–10PFU/ml. The short- and long-term ecology of local soil microbial communities may be impacted by the use of phages since the soil ecosystem provides a suitable template for phage–bacterial interactions. The soil rhizosphere is modulated by exudates from plant roots that allow the development of bacterial populations and interaction with phages. Phages likely regulate host populations by lysis but may compensate by having longer lysogenic stages that prevent further infection and lysis. Phages appear to be large reservoirs of genes that encode proteins that may be novel to any bacterial strain. Studies with both virulent and lysogenic phage gene sequences show that phage–bacterial interactions that occur in soil permit genetic exchange from one host to another. The exchanges may involve the exchange of genetic material via lysogeny, lytic action, abortive infections, transduction, and pseudolysogeny.
The chapter presents three specific case studies that highlight interaction between indigenous soil bacteria, plant pathogens or symbionts (Erwinia amylovora, Pectobacterium carotovorum, and Rhizobacteria), and bacteriophages applied as biological control agents. In addition, we address the special role of lysogeny in the soil–phage interactions and the current methods employed for the detection of phages in the soil.
Keywords
Phage Type Fire Blight Bacterial Host Orchard Soil Pectobacterium CarotovorumReferences
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