Enhancement of Stress Tolerance in Vitis vinifera

Abiotic stresses affect important aroma, flavor and color components by altering metabolite composition, improving wine quality and human health benefits. Regulated deficit irrigation has been used successfully to grow grapes with less water, an important feature in arid regions such as Nevada. As a first step toward understanding how growth is affected and wine quality improvements might arise following abiotic stress exposure, we have initiated an expressed sequence tag (EST)-based gene discovery program focused solely on stressed plants. We constructed cDNA libraries from mRNA isolated from leaf, berry and root tissues of Vitis vinifera cv. Chardonnay, exposed to various abiotic stress conditions. To date, we have met our goals for the last two years and sequenced more than 20,000 ESTs, approximately 6,700 each from the leaf and berry libraries and 9,500 from the root libraries. Raw sequence data were processed through an automated EST analysis pipeline (ESTAP) developed at the Virginia Bioinformatics Institute (VBI; Blacksburg, VA) in collaboration with UNR and S.R. Noble Foundation (Ardmore, OK). Initial sequence analysis revealed approximately 50%novel or functionally unknown genes and a low redundancy of transcripts (38%). All EST data generated to date from leaf and berry libraries have been deposited in GenBank and are freely available to the public at the NCBI dbEST and ESTAP websites. Data from root libraries is currently being subjected to rigorous cleansing to avoid deposition of EST data from contaminating soil microorganisms.