Plant roots excrete a variety of metabolites into the rhizosphere and create unique habitats for the microbial communities. The microbes exchange their metabolites and significantly impact plant physiology through symbiosis and virulence. Recent metagenomic studies have expanded the catalog of genomic information of the microbiome across diverse plant species and soil environments. However, much less is studied about the molecular mechanisms underlying the formation of these microbial ecosystems. To understand the basis of plant-microbial interactions, my research focuses on developing novel experimental approaches and identifying the quantitative links from genotype to phenotype. I will combine a careful characterization of rhizobacterial physiology with a spectrum of advanced capabilities at Berkeley Lab, including functional genomics, genome engineering, and laboratory automation.