The factors that control genetic transmission in populations determine the course of evolutionary change. This research project is concerned with the transmission of a series of genes that control flower color variants in the common morning glory. The project is also concerned with the molecular events that produce different flower color types. Previous work has shown that several ecological factors interact with morning glory reproductive biology to cause the differential transmission of white and pigmented color variants. Counter balancing these selective forces are high rates of mutation at the gene loci that determine white color. Dr. Clegg has shown that these high mutation rates are most probably the result of transposable elements that disrupt gene function at the white locus. The proposed work seeks to further investigate the molecular bases of flower color variation. To accomplish this goal the investigators have begun a molecular analysis of variation at the locus that encodes CHS, a key enzyme in pigment biosynthesis. Earlier work indicates that the white type is the result of a mutation at the CHS locus. Several copies of the CHS gene have been cloned using the methods of recombinant DNA technology. Dr. Clegg now seeks to build on this foundation through genetic and molecular analyses. The proposed research should fill in a void in basic knowledge of the dynamics of gene transfer. From an applied agricultural perspective, it is important to have a detailed understanding of the nature of mutational diversity in plant species. The proposed work will contribute to this understanding by characterizing the nature of molecular diversity in plant genes.***
