BREAKING BUD DORMANCY IN GRAPEVINES WITH GARLIC PASTE

Four dormant grapevine (Vitis spp.) cultivars grown under forced conditions were treated immediately after pruning with a paste of fresh garlic, the supernatant of a 20% suspension of CaCN2, and 50% 'Merit' solution, a foliar fertilizer, to break bud dormancy. Garlic paste significantly accelerated budbreak and increased the rate of budbreak in three cultivars, but for 'Delaware,' CaCN2 was more effective. Garlic also affected budbreak of cuttings with a single bud of 'Kyoho,' 'Neo Muscat,' or 'Muscat Bailey A' grapes in a deep stage of dormancy. Garlic paste applied to cool 'Muscat of Alexandria' vines immediately after they were pruned in various stages of dormancy (from November to March) accelerated budbreak in the spring when application was made by January. The rate of budbreak was steady, but earlier CaCN2 treatments resulted in a rate of budbreak that was not uniform, although the first budbreak was accelerated. Low concentrations of garlic juice did not promote budbreak of cuttings of 'Muscat of Alexandria'. When garlic paste was applied to various parts of cuttings with two buds, budbreak was accelerated when the upper cross-section was treated, but the overall rate of budbreak was highest when the lower half of the cutting was treated. Chemical name used: calcium cyanamide (CaCN2).