Different rates of hydrogen cyanamide in bud break of 'Rocha' pear tree

With the objective of evaluating the effect of hydrogen cyanamide on the percentage and rate of bud break of 'Rocha', an experiment was conducted in an orchard located in Lages, southern Brazilian region. The buds were submitted to different treatments to overcome dormancy, which consisted of different doses of hydrogen cyanamide (0.5, 1.0 and 1.5%) plus 3% mineral oil, and a control treatment sprayed only with water. The experimental design was a randomized blocks with six replicates. There were four evaluations: 15, 22, 29, and 37 days after application of the products to account for bud break. The data were analyzed for their variance and to verify the polynomial regression between the doses tested. The effect of hydrogen cyanamide at the concentration of 1.5+3% mineral oil increased bud break by 40.20% compared to the control treatment and advanced bud break, reaching 25% at 15 days after application of the product. The cultivar 'Rocha' responded to induction and the highest dose used gave the highest percentage of bud break.