Bud break and enzymatic activity in buds of grapevines cv. Ives treated with Gallesia integrifolia hydrolate

Abstract

The lack of more sustainable options for inducing bud break in grapevines in mild winter regions is a limiting factor for local viticulture due to restrictions on the use of agrochemicals. Within this context, an experiment was conducted to evaluate the effects of a hydrolate obtained from Gallesia integrifolia (a native Brazilian tree) on the bud break of grapevines cv. Ives. The experiment was conducted in a vineyard located in Marialva, Parana, Brazil, over two consecutive crop cycles: 2011 (September/December) and 2012 (February/May). The treatments consisted of the following doses of Gallesia hydrolate (GH): 0, 100, 150, 200, and 250 mL L−1, as well as 30 mL L−1 of garlic extract and 20 mL L−1 of hydrogen cyanamide, which were used as positive controls. The following variables were evaluated: sprouting percentage per plant, number of clusters per plant, cluster mass, yield (t ha−1), catalase and peroxidase activities. The GH treatments improved bud break in cv. Ives during both crop cycles, demonstrating quadratic effects relative to the applied doses. The same effect was verified for the number of clusters and for the yield. Twenty-four hours after the treatments, a quadratic effect for peroxidase and catalase activity was verified relative to the GH doses applied. For peroxidase activity, the treatment at 200 mL L−1 GH resulted in a 57 % reduction relative to the control. The most abundant component found in GH was dimethyl disulfide. Based on these results, GH at 150 mL L−1 could be a promising alternative to the currently used methods for promoting bud break in cv. Ives, representing a cheaper and more environmentally friendly option for viticulture.