Molecular tools for clone identification: the case of the grapevine cultivar “Traminer”

In viticulture, biotype identification problems have traditionally beensolved using ampelography, ampelometry and chemical traits analysis.However, these tools have resulted in several false attributions, inparticular when used at the clonal level. The availability of relativelycheap, reliable and reproducible tools to identify genetic differences atthe clonal level would greatly facilitate the work of clonal patenting. Inthis work, 24 accessions of Traminer cultivars were characterizedusing molecular markers. Three different approaches were applied:simple sequence repeats (SSR), amplified fragment length polymorphism(AFLP) and methyl-sensitive amplified length polymorphism(MSAP). Results showed that SSRs were not a powerful tool for clonaldistinction. In contrast, the AFLP technique was able to distinguish 16out of the 24 cultivars, even though the average similarity was high(97.1%). The MSAP technique was used to evaluate qualitativedifferences in the degree of DNA methylation among clones. Resultssuggest that morphological differences among clones are probably dueto the synergetic effect of genetic and epigenetic modifications, andthat clonal identification could be greatly improved using moleculartools such as AFLP and MSAP.