The Rock Grape (Vitis rupestris Scheele)
Vitis rupestris (Rock grape) has become an important genetic resource for viticulture ever since grape growers started grafting grapevines on rootstocks in the 19th century. The species first became known as a rootstock with strong and durable resistance to phylloxera. Later, V. rupestris was also recognized as a rich source of genes for resistance to diseases such as black rot, powdery mildew, and downy mildew, and for tolerance to drought and soil salinity. The species has experienced a dramatic decline in geographic range over the past century. We have recently collected and propagated plants from the Ozark and Ouachita Mountains to assess the genetic diversity of extant populations. The photo to the right depicts a V. rupestris shrub growing in its native habitat in the Ozarks. It typically colonizes nutrient poor gravel bars and rocky banks along rivers and intermittent streams. Below are scanned images of a mature leaf and a shoot tip from 35 accessions from our collection.
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