This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).
Polyploidy (whole genome duplication) is one of the most important genetic phenomena in plants. Immediately after its formation, a polyploid plant can be identified simply by counting its chromosomes, because it has twice as many as a diploid. However, after millions of years a polyploid may have as low a chromosome number as a diploid through a process called "diploidization." Genomic studies can detect such cryptic polyploids, and the advent of high-throughput sequencing has made this approach increasingly feasible. Using this new technology, this project will estimate the frequency of polyploidy in the phaseoloid legumes, a group that includes soybean, common bean, cowpea, pigeonpea, and other less familiar crops, by sequencing thousands of transcribed genes from approximately 25 phylogenetically diverse species. Polyploid events will be identified by their characteristic signature, an excess of genes with two copies duplicated at the same time.
The project has broad significance for genetics and systematics, given the importance of polyploidy as a genetic phenomenon, and also for agriculture, because polyploidy is so common among crop plants (e.g., soybean, wheat, maize, cotton). The large numbers of genes will be a resource for subsequent studies in this large and important lineage. A talented female postdoctoral associate will receive training in the generation and analysis of next-generation sequencing data.