Limited knowledge of the origins and evolution of weedy characteristics of monocots limits the formulation of novel genetic strategies to improve crop productivity. Given the high degree of seed dormancy, seed shattering, and many other weedy characteristics in wild grasses, red rice (a noxious weed in rice growing areas of Southern United States), as a model, provides a simple genome structure and availability of enormous genomic resources (e.g. integrated high density genetic and physical map, expressed sequence tags, and whole genome sequences) for molecular dissection of these complex adaptive physiological traits. Compared with the standard mapping population strategies commonly used to determine quantitative trait loci (QTL), introgression line (IL) populations represent a better alternative because of their increased efficiency, immortality and the added advantage of fast-tracking the genome-wide gene discovery process. Preliminary research has determined that red rice ecotypes exhibit a high degree of DNA polymorphism and striking differences in several key domestication-related traits, compared with cultivated rice “Cypress”. Therefore, the primary goal of this proposal is to elucidate the molecular genetic basis of weediness in red rice, with special emphasis on seed dormancy and seed shattering, which are two key traits for survival and persistence of the majority of weed species.