conference schedule and program with abstracts - Horticulture ...

O-48
Discrimination of grapevine clones by methylation sensitive AFLP analysis
S. Lang 1 , G. Buchholz 1 , G. Brendel 2 , F. Regner 3 , G.M. Reustle* 1
1 RLP AgroScience GmbH, Neustadt / Weinstraße, Germany; 2 Rebschule Steinmann e.K.,
Sommerhausen, Germany; 3 Höhere Bundeslehranstalt für Wein- und Obstbau Klosterneuburg,
Klosterneuburg, Germany
*Corresponding author: goetz.reustle@agroscience.rlp.de
The European wine market is the most competitive market worldwide. To maintain the
competitiveness of the domestic wine industry, availability of appropriate grapevine clones that
meet the present demands of viticulture and wine market is important. However, selection and
set-up of a new clone is time-consuming and expensive. Discrimination of clones is important
for germplasm maintenance, breeding and certification. For breeders, identification of their
clones is a pre-requisite to claim property rights and to assure the return of invest by licence fees.
Grapevine varieties are traditionally identified by morphological and morphometric descriptors.
During recent years, molecular marker technology has been used successfully for genetic
diversity studies as well as cultivar differentiation in grapes. However, distinction of clones
within a variety is difficult. Even differences described by breeders after many years of clonal
selection cannot be detected using the new molecular methods. It is assumed that the different
behaviour of clones of a variety can be explained by mutations, having accumulated over the
years, but it could be also due to non-mutagenetic changes in gene regulation. In the latter case,
the DNA-sequences are identical but the phenotypes could be different, due to the methylation of
regulatory elements or coding sequences (epigenetic changes). One of the most powerful
molecular marker technologies is the Amplified Fragment Length Polymorphism (AFLP)
approach. In the project presented, methylation sensitive primers are used in the AFLP to
identify clones by different specific methylation patterns. The results showed that methylationsensitive
AFLP allows the differentiation of clones of the rootstock SO4 and of the variety
Silvaner, independent from location, physiological age and year of sampling. On the basis of
these results, six primer combinations (PC) were selected for rootstocks and varieties
respectively, yielding clone specific markers. With these primer combinations clone-specific
epigenetic markers were also identified for clones of Grüner Veltliner and of Kober 5BB. The
data obtained so far confirm that epigenetic changes are also responsible for diversity within
grapevine varieties, in addition to stable mutations and transposon activity. Investigations on
correlation of epigenetic markers and a particular phenotype are projected.
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