FINDING ALTERNATIVES FOR DORMEX (HYDROGEN CYANAMID) AS DORMANCY BREAKING AGENT

Several studies reported the beneficial effect of Dormex (Hydrogen Cyanamid) on compensating the lack of chilling hours required for a normal vines budburst. It was recently prohibited in many countries due to its toxicity on plants and humans. The objective of this study was to find alternatives for Dormex. Gibberellic acid plays a role as endogenous hormone on budburst. Nano-fertilizers (Amino25) are known to prevent biotic and abiotic stresses in plant. No studies were conducted on the effect of both products on vines in warm winter climate. Two experiments will be discussed in this paper and compared to previous result of Dormex applied at the same location. The treatments were: Openfield/Without Products, Greenhouse/Without Products, Open-field/Gibberellic acid, Greenhouse/Gibberellic acid, Open-field/Amino25 and Greenhouse/Amino25. The study was conducted on three ARRA seedless cultivars. Gibberllic acid was applied at 2ppm and Amino25 were applied at 1.5 g L-1 for several times before budburst. Giberellic acid enhanced bud formation under greenhouse as Dormex did and induced earliness of 2 weeks in budburst while its effect on fruits, flowers and yield was less efficient than Dormex. It did not have effect in open-field conditions as well as Amino25 in both cultivation systems. Gibberellic acid could replace Dormex to resolve bud burst problem. Since Gibberellic acid and Nano-fertilizers are non-toxic and could be used on organic farming, advanced research should take place to enhance the effects of Gibberellic acid in open-field conditions and additional studies are recommended regarding the effect of Nano-fertilizers on grapevines.