Capacity for microbial biomass to be used in biological control to manage plant pathogen growth: advancement of pseudomonas flourescens strain wayne1r as a biocontrol agent through identification of novel biocontrol genes

Seth A. Maurer, The College of Wooster


Bacterial strains isolated from the soil around plant roots, the rhizosphere, have been shown to greatly influence the growth of a host plant. These bacteria can be Plant Growth Promoting Rhizobacteria and directly stimulate plant growth, inhibit plant pathogens by secreting anti-pathogenic molecules or competition through biological control, or participate in both processes. One novel bacterial strain recently isolated from the rhizosphere, Pseudomonas flourescens strain Wayne1R, has been found to inhibit several plant pathogens, including Rhizoctonia solani, a prevalent fungi. In order to further the advancement of Wayne1R and other bacterial species as biocontrol agents, novel biological control genes need to be determined. To identify novel biological control genes is Wayne1R cells, as well as other biological control agents, random mutagenesis of the Wayne1R genomic DNA was attempted using a transposome kit and tri-parental mating. After the transposome kits proved to be unsuccessful, the tri-parental mating procedure produced over 500 putative mutants. The putative mutants were screened for their ability to inhibit R. solani and every putative mutant showed a complete loss in function. Ultimately, upon screening of the putative mutants and amplification of a Wayne1R specific gene through colony-PCR, it was determined that the putative mutants were most likely some form of contamination and not mutated Wayne1R cells of interest.


© Copyright 2010 Seth A. Maurer