Microbes living in the plant rhizosphere, the soil in direct contact with a plant's roots, influence nutrient cycling and availability, the plant's susceptibility to disease, and plant growth. Plant roots, in turn, provide resources that support the microbial community, and produce signals that affect plant-microbial interactions. Currently, little is known about the genes and biochemical pathways in plants that influence the development of specific rhizosphere communities, nor the impact that these communities have on the growth, reproduction and competitive ability of plants. Using Arabidopsis thaliana and an important domesticated species, lettuce, and its wild, weedy progenitor (Lactuca serriola), the investigators will identify key genes in plants that affect the microbial communities in the rhizosphere. Specifically, the project will: 1) characterize the composition, successional patterns and robustness of the microbial communities that establish in the rhizosphere of specific plant genotypes; 2) identify quantitative trait loci and candidate genes in the plants that control the differences in microbial populations associated with roots; 3) examine the impact of these plant-microbe interactions on growth and the competitive abilities of plants. This project will cement a multi-investigator research initiative that will enhance student training and engage faculty in multidisciplinary research and teaching. University of Massachusetts, Boston has a high proportion of low income, under-represented minority and first generation college students, and the investigators are dedicated to their training. Research initiatives developed in this project will be integrated into several active training programs aimed at community college students, secondary school teacher training and enhanced undergraduate research experiences. Project results will advance the understanding of how plant-microbe interactions alter the soil quality and growing conditions of plants, and demonstrate the relevance of rhizosphere ecology to a broad cluster of applied disciplines, from sustainable agriculture to restoration ecology and management of invasive species.
