GENE TRANSFER FOR STRESS RESISTANCE IN GRAPES

Biotic and abiotic stress significantly increases the negative effects on both quantity and quality of grape production. Like a many woody crops, grape has been relatively recalcitrant to in vitro manipulations. The crucial point in the process of genetic transformation is to have cells both to be able to regenerate and to be transformed. Regeneration system appears to be major problem in transforming grape. Somatic embryogenesis favoured regenerative protocol in genetic transformation of grapes. Comparison of an embryogenic system with an organogenic one in grape demonstrated that organogenesis frequently leads to chimerical transformation tissues. In this respect we started to develop and apply procedures suitable for the genetic transformation of grapevine. Two sources of explants were used for embryo induction. In the case of Vitis vinifera seedless genotypes-immature zygotic ovules. In second case in vivo leaf tissues of rootstock Vitis rupestris cv. Rupestris du Lot and 110 Richter (Vitis Berlandieri x Vitis rupestris). Embryogenic cultures have been maintained either by continual transfer on fresh medium. We used Agrobacterium tumefaciens like a vector to transform emryogenic cultures of seedless grapes (Vitis vinifera L.) with construct carrying the gene of coat protein of GFLV (Grape Fanleaf Virus) and with 4 constructs containing antifreezing genes. Embryogenic culture of rootstock Vitis rupestris cv. Rupestris du Lot was transformed with construct carrying -glucoronidase (GUS) gene. The first transforming plantlets have been regenerated from somatic embryos. Presence of the NPT II gene was verified by PCR and Southern blot analyses. Propagation and following tests are in progress.