Scientific Note Compounds Derived from Garlic as Bud Induction Agents in Organic Farming of Table Grape

Viticulture is one of the most important economic activities in the Northwest of Mexico. A major obstacle for the economic production is the insufficient period of chilling temperatures. This problem leads to poor budbreak, which in turn results in reduced yields. This problem is aggravated when plants are cultivated using the organic farming system, mostly because there are not organically approved restbreaking agents. In this work different products derived from garlic (Allium sativum L.) were obtained and evaluated as stimulate budbreak agent of table grape (Vitis vinifera L.) cvs. Flame Seedless and Perlette. The isolated compounds were chemically identified and include allicin, diallyl disulfide, diallyl trisulfide, 3-vynil-[4H]1.2-ditiin and 2-vynil-[3H]-1.3-ditiin, S-methyl cysteine sulphoxide, dimethyl disulfide, dimethyl trisulfide and dimethyl thiosulfonate. Cuttings with six buds were used to evaluate the compounds. After compounds were applied, the cuttings were transferred to a growing chamber at 24 °C. All evaluated compounds promoted budbreak in the cuttings of Flame Seedless and Perlette. The volatile compounds from S-methyl cysteine sulfoxide promoted 100% of budbreak of both cultivars. The compounds from garlic that stimulated budbreak in grapevines in this work include sulphur in their molecule; therefore we propose that sulphur could play a key role in breaking bud dormancy of grape cultivars evaluated in this study.