Conserving and utilizing intra-varietal variation in grapevines ( Vitis vinifera L.)

Abstract

Climate change poses a major challenge to grapevine growing and breeding. Higher temperatures and altered rain patterns will result in a shift of varieties to other areas or require the adaptation of varieties in their traditional growing regions. A large intra-varietal variation is a prerequisite for this task. Clonal selection is an important part of genetic improvement in grapevines. In contrast to cross breeding, it depends on the already existing genetic diversity within a variety. Due to their age, genetic diversity in traditional varieties can be quite large, providing the basis for new clones, better suited to altered climatic conditions and industry demands. In Germany clonal selection commenced already at the end of the 19th century, presumably due to the fact that under its cool climatic conditions virus infection, in particular fanleaf reduces crop dramatically. These first attempts were so successful that they were copied by numerous private and public breeders, and since the mid-1950 s virtually only clonal material is being planted.