Distinguishing Carmenère from Similar Cultivars by DNA Typing

A total of 93 vines from five vineyards in Chile that were originally planted as Merlot, four vines from a cultivar collection in Chile, and two vines in California were analyzed with SSR DNA markers to confirm their identity. DNA profiles were compared to those of previously confirmed reference vines. Vines in the Chilean vineyards matched the DNA profiles of either Merlot or Carmenère, consistent with prior visual identification of these vines. The four vines from the cultivar collection matched Carmenère, although they were originally planted as Merlot. Both California vines were confirmed as Carmenère, although one was originally imported as Cabernet franc. Two markers, VVMD28 and VVMD31, are particularly useful for distinguishing Carmenère from Merlot. VVMD31 will also distinguish Cabernet franc from the other two cultivars, as will VVMD27. Although these three cultivars can be distinguished visually, DNA typing is a valuable adjunct for verifying identity, particularly for vines in nurseries and foundation plantings.