Proceedings of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress

Giardini Naxos, Italy - 18/21 September, 2002

ISBN 88-900622-3-1

Poster Abstract - 1.22

PRELIMINARY RESULTS FOR IMPROVEMENT OF GRAPEVINE USING GENETIC TRANSFORMATION

GHIANI A., CASAZZA G., BORLOTTI A., ROSSONI M., SCIENZA A.

Dipartimento di Produzione Vegetale, Università degli Studi di Milano, Via Caloria 2, 20133 Milano, Italia

grapevine, transformation, salt stress, resveratol

Grapevine (Vitis spp.) is one the most important fruit crops throughout the temperate regions of the world. In particular, in Italy grape is of special interest because of its high “cultural” and economic value. Improvement of this crop is possible by traditional breeding but this is rather difficult and time-consuming because of the too long generation cycle, high levels of heterozygosity, and imbreeding depression which prohibits selfing. Futhermore, genetic transformation techniques could be an alternative solution to genetic improvement of grapevine. The major advantage of genetic techniques is the ability to direct improvement of important cultivars without altering their essential features.

In particular we are focusing on two different projects for genetic transformation of grapevine:

1) transformation for improving agronomic attributes of the grapevine using genes that could confer salt stress resistance as, CodA gene and AVP1 gene

2) transformation for improving both agronomic attributes and food quality characteristics of grapevine using a gene that could increase the production of resveratrol, a phytoalexin produced in grapevine and in few other plants in response to injury.

CodA gene from Arthrobacter globiformis encodes choline oxidase, the enzyme that synthetizes glycinebetaine, a compound with osmoprotectant properties, from choline.

AVP1 gene from Arabidopsis thaliana, encodes for the vacuolar H⁺-pyrophosphatase. Increasing the vacuolar proton gradient results in increased solute accumulation and water retention.

To increase the production of resveratrol in grapevine a possible solution is the overespression of the stylben synthase, an enzyme found in a few plant species which synthesized the phytoalexin trans-resveratrol using substrates commonly present in plants.

We have prepared several gene constructs, either for salt stress tolerance and for increase the production of resveratrol, incorporating also the green fluorescent protein (GFP) or the bar gene or the manA gene as marker genes.

At the present day we have used these constructs to transform also Nicotiana tabacum.