962359 Abstract Self-incompatibility (SI) loci have become model systems for studying the role of selection in maintaining genetic diversity. SI is a genetic system which prevents inbreeding in many plant species. Research funded by this award will advance knowledge on the genetics of self- incompatibility through examination of how these systems are organized at molecular, phenotypic and, populational levels. The relationship of molecular variation to the expression of incompatibility types will be determined through controlled breeding experiments. These relationships will provide invaluable information linking complex phenotypes to DNA sequence variation, increasing our knowledge of how complex biological mechanisms are coded in the DNA. Findings from several wild populations will be integrated analytically to understand the origins and distribution of genetic diversity within the species. This work will be accomplished using the wild tomato species, Lycopersicon chilense. Lycopersicon chilense represents a close relative to domesticated tomatoes and a valuable source of potential germplasm for this important crop. Genes identified in this research could be of direct utility in manipulating the breeding system and pollination mechanism of domestic tomatoes.
