Genetic characterization of closely related rootstocks varieties based on AFLP and SAMPL markers

Resumen

Breeding and selection of different rootstock varieties enables winegrowers to plant vine on different soil types and under different climate conditions. Furthermore rootstocks are a perfect biological barrier for a wide range of pests, such as phylloxera. For these reasons it is very important to accurately certify the rootstock variety used. Commonly the variety of rootstock cuttings is checked by rooting and planting them and assessing the morphology of the grown shoot. With disbudded rootstock cuttings this method is not possible nor can it be applied to already grafted vines. High-throughput marker techniques can be used to differentiate even closely related grapevine varieties. The description of the genetic characterization of rootstock varieties with equal crossing heritage is based on AFLP- and SAMPL-markers. We analyzed 5 BB, SO 4, 5 C and Binova rootstock varieties, using four AFLP and four SAMPL primer combinations. We detected rootstock-specific amplified fragments for the rootstock varieties 5 BB, SO 4 and 5 C, which could be clearly distinguished. SO 4 and Binova rootstock varieties could only be differentiated by flower morphology, as SO 4 is male and Binova is hermaphrodite. Previous molecular analysis of SO 4 and Binova did not allow their discrimination. No polymorphism was observed between Binova and SO 4 clones using high-throughput markers. This result suggests Binova may be a somatic mutant of the rootstock variety SO 4. A total of 30 accessions belonging to 5 BB (13 plants), SO 4 (6 plants) and 5 C (11 plants) were characterized to study intravarietal variability. Both recurrent bands within one rootstock variety and single bands specific for a single accession were observed and will be further discussed in this poster.