Conservation of the genetic resources of Vitis

As an alternative or supplement to field collections, a repository of 35 grapevine genotypes and 15 clones of cv. Optima was set up under minimal growth conditions. To prolong the storage period between subculturing to at least 12-18 months, some factors of long-term storage were optimized and the causes responsible for early senescence of sensitive genotypes were investigated Besides indirect effects due to excision time, origin of the starting material and preculture, there is a direct influence of the light conditions on the survival rate of cultures. CCC application showed, in some cases, positive effects only after long-term storage. An increase of carbon dioxide concentration during storage is considered to be responsible for the early death of some cultures.