The most important traits in agriculture, medicine, evolution, and ecology have a complex genetic basis. Significant progress has been made recently toward estimating the number of genes that control these traits and the effects of individual genes. To understand how trait differences become established between species, however, the effects of these genes on viability and reproductive output (i.e., fitness) must be determined in natural populations. In this proposal, both genetic and ecological approaches will be employed to estimate the fitness effects of eight genes (or small chromosomal segments that contain them) that control differences between two sunflower species. The validity of these estimates will be verified by analyzing the movement of these genes between the two species when they hybridize in nature.
The proposed activities are anticipated to have broader impacts through research training of underrepresented groups, undergraduate and graduate students, and postdoctoral scholars. In addition, the genetic materials created in this grant will be made freely available to other researchers. Sunflower is the only major crop plant domesticated in the U.S., and the traits chosen for study are important both to the diversification of wild sunflower species and to the domestication and continued improvement of the cultivated sunflower.
