S-TYPE BACTERIOCINS AND THE COLONIZATION AND SURVIVAL OF PSEUDOMONAS SYRINGAE PV. TOMATO IN THE PHYLLOSPHERE

The overal goal addressed by theobjectives ofthis projectisto understand the role s-type bacteriocins play in epiphytic colonization and survival, to gain insight into ecologically important factors that lead to disease.Since foliar pathogens, such asP. syringae, must first invade, persist, proliferate within an epiphytic context prior to invasion into the leaf interior, understanding how pathogens compete within a community context will provide insight into how best to take advantage of communities to block initial colonization of the pathogen.Objective 1- Invading:Assess level of foliar disease symptoms(Obj 1.1)in tomato plants determine the differences in microbial community composition(Obj 1.2)due to individual s-type bacteriocins inpto, after transplant communities are introduced to plants that have first been inoculated withpto.The purpose of this objective is to identify how bacteriocins contribute to disease severity and microbial community compositionafterptohas penetrated the leaf surface. I expect that some s-type bacteriocins will have a positive benefit for pathogen invasion and lead to greater disease and more pathogen on the surface ofthe leaf than the negative controls. I expect that s-type bacteriocins will contribute to significant differences in community composition after 7 days.Objective 2-Defending:Assess the level of foliar disease symptoms(Obj 2.1)in tomato plants and determine the differences in microbial community composition(Obj. 2.2) due to individual s-type bacteriocinsafter pto is introduced to a plant that has an established microbial transplant community. The purpose of this objective is to identifyptobacteriocins that contribute to disease severity of bacterial speck of tomato and identify microbial community changes due toptobacteriocinsbeforeptohas penetrated the leaf surface. I expect that some s-type bacteriocins will have a positive benefit for pathogen niche defense and lead to greater disease and greaterpathogen populations on the surface of the leaf than the negative controls. I expect that s-type bacteriocins will contribute to significant differences in community composition after 7 days.