Submitted to: Conservation Genetics
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/22/2008
Publication Date: 2/10/2008
Citation: Wang, M.L., Jorge, M., Morris, J.B., Zhenbang, C., Barkley, N.L., Pederson, G.A.Evaluation of Lespedeza Germplasm Genetic Diversity and Its Phylogenetic Relationship with the Genus Kummerowia. Conservation Genetics: 10:79-85. 2009 DOI 10.1007/s10592-008-9524-2
Interpretive Summary: The genus Lespedeza contains approximately 40 annual and perennial species. These species have been used as forage crop, ornamentals, and medicinal plants. There is a big collection of Lespedeza in the Plant Genetic Resources Conservation Unit (PGRCU), USDA-ARS at Griffin, Georgia. These accessions have never been characterized and classified morphologically and genetically. Forty-five Lespedeza accessions and three other related species with Lespedeza were used in this study. They were genotyped with DNA markers and classified into three clusters and eight subgroups. Some misidentified accessions were found. Misidentified accessions were reexamined by morphological observation and reclassified into other species. Information on genotyped Lespedeza accessions would be useful for forage curators, breeders and other scientists.
Technical Abstract: The genetic diversity of the genus Lespedeza is not well known and the phylogenetic relationship of Lespedeza with the genus Kummerowia is unclear. We report the first study in which polymorphic expressed sequence tag-simple sequence repeat (EST-SSR) markers derived from Medicago, cowpea and soybean were used to assess the genetic diversity of the Lespedeza germplasm collection and clarify its phylogenetic relationship with the genus Kummerowia. Phylogenetic analysis partitioned 44 Lespedeza accessions into three main groups, some of which were species-specific and eight subgroups. This data set revealed some misidentified accessions, and indicated that two species in the genus Kummerowia are closely related to the genus Lespedeza. Morphological reexamination was used to correct the misidentified accessions within the genus Lespedeza. Our results demonstrated that phylogenetic analysis with morphological reexamination provides a more complete approach to classify accessions in a plant germplasm collection.