Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: 3/19/1998
Publication Date: N/A
Technical Abstract: The USDA-ARS manages a network of ex situ germplasm collections for most U.S. crops. These collections support crop improvement and conservation activities. Currently, the germplasm repository system in the U.S. is overburdened. No in situ preserves for genetic resources exist in the USDA-ARS germplasm system. Complementary in situ reserves would ensure that evolutionary dynamic forces continue to influence plant adaptation. We are working to establish conservation priorities for wild American Vitis species and to designate in situ preserves. With a geographic range declining due to loss of habitat, rock grape, Vitis rupestris Scheele, is a candidate species for in situ preservation. Rock grape was studied at 19 populations in nine states during 1997. Morphological and molecular analyses emphasize different characteristics for prioritizing populations during the planning of in situ preserves. There was significant morphological variation among and within these populations for all measured variables (MANOVA, post-hoc tests, and Fisher's exact test). Morphological analyses suggest that in situ preserves may be necessary in the western, central, and eastern parts of rock grape's range. DNA samples were screened at four microsatellites. Genetic diversity measures and UPGMA dendrograms indicated that additional populations needed to be considered for in situ preserves. Characterizing genetic diversity and its distribution throughout species' ranges enhances our understanding of adaptation and survival of wild species and ensures that genetic resources are available for study or use in breeding programs.