XVI International Botanical Congess

Using Arabidopsis thaliana as a model system, we, and others, have identified mutants in at least seventeen different genetic loci regulating ovule development. Effects of these mutations include elimination, loss of identity, or proportional changes in ovule substructures. Some of these mutants mimic specific evolutionary events in ovule phylogeny, suggesting that evolution of these loci may be associated with ovule diversification. Through morphological studies and analyses of double-mutant lines we have assembled a preliminary model for genetic regulation of ovule development. Our results illuminate specific genetically regulated steps in this process, enable studies on molecular mechanisms of ovule ontogeny, and may help elucidate the natural history of the ovule. Supported by NSF and the USDA/NRICGP.