|PAP, DANIEL - Missouri State University|
|MILLER, ALLISON - St Louis University|
|KOVACS, LASZLO - Missouri State University|
Submitted to: American Journal of Enology and Viticulture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/4/2015
Publication Date: 11/1/2015
Citation: Pap, D., Miller, A., Londo, J.P., Kovacs, L. 2015. Population structure of Vitis rupestris, an important resource for viticulture. American Journal of Enology and Viticulture. 66:403-410.
Interpretive Summary: The purpose of this study is to document population genetic variation in the rock grape (Vitis rupestris). During the past 150 years, V. rupestris has become a key source for the development of stress-tolerant and pest-resistant rootstocks, as well as disease-resistant fruit-bearing grape varieties in breeding programs around the world. Recently, this species has undergone rapid decline across its native range in central and eastern North America. Using DNA markers, researchers examined the genetic structure of wild rock grape populations on the Ozark Plateau in Missouri and the Ouachita Mountains in Oklahoma where it still grows in relatively large numbers. Our data showed these plants live in two geographically isolated groups (Missouri and Oklahoma), and populations within Missouri are only moderately differentiated from one another. Regardless, all populations surveyed contain population-specific variants of genes. Further genetic and ecological studies are required to better understand population dynamics in this species and to safeguard against loss of its valuable genetic diversity.
Technical Abstract: The wild North American grapevine Vitis rupestris Scheele is an important genetic resource for viticulture, but its natural population has been severely depleted. We collected samples from seven V. rupestris populations from the Ozark Plateau in Missouri and Ouachita Mountains in Oklahoma and genotyped them with 14 microsatellite markers to assess allelic diversity, heterozygosity, and genetic differentiation at various levels of population structure. We found that genetic diversity in V. rupestris was similar to that in other grapevine species and in other outcrossing angiosperms. We detected significant genetic differentiation among populations (FPT = 0.105) and no significant deviation from Hardy-Weinberg equlibrium in some populations, but moderate inbreeding in others. Pronounced differentiation between Missouri and Oklahoma populations was supported by STRUCTURE and principle coordinate analyses, and was apparently a function of geographic distance. Genetic differentiation among Missouri populations was modest. We posit that population differentiation and genetic drift may be inherent features of V. rupestris.