Characterizing the Genetic, Phenotypic and Soil Diversity Associated with Natural Populations of Setaria viridis

Soil variables are major factors that determine a plants access to water, nutrients and association with microbiota. As an evolutionary force, qualities such as mineral composition, reactivity (pH) and texture influence the geospatial distribution of plant species. The primary goal of this study is to catalog the genetic and physiological diversity of Setaria viridis natural accessions and examine how these characteristics are associated with soil variables at their collection site. To achieve this objective we have developed a genetically diverse collection of Setaria viridis ecotypes and empirically determined several major chemical characteristics of their native soil. Genetic analysis of polymorphisms identified using genotyping by sequencing suggests the presence of 2-3 distinct genetic populations within this sample and phenotypic associations within the genetic structure of the population. Values of pH and electrical conductivity determined from soil obtained at each collection site exhibit a significant positive correlation with corresponding values downloaded from the SSURGO database. Our efforts focused on screening this population for salinity tolerance through development of an inexpensive, scalable phenotyping system (automated irrigation and image capture) is also discussed.