EFFECT OF HYDROGEN CYANAMIDE ON BUDBREAK AND OTHER GROWTH PARAMETERS IN DIFFERENT GENOTYPES OF GRAPES

摘要

ONE of the major problems confronting the grape growers is poor budbreak, which results in the low productivity. Even though the buds are potentially productive, their capacity cannot be exploited because of supression of budburst. Application of hydrogen cyanamide 2.0 per cent a. i. was found to be optimum to increase the bud break in Thompson Seedless cultivar of grape of (Manjunatha, 1990). The availability of information on the effect of hydrogen cyanamide on budreak, subsequent shoot growth andbunch development is limited to a very few cultivars of grapes. Elucidation of such information in different genotypes is very much essential. Based on their response to hydrogen cyanamide, desirable genotypes could be identifieed and utilized for further breeding programme. A field trial was carried out on sixteen grapevine genotypes of seven year age, with an objective of elucidating the effect of Hydrogen cyanamide at 2.0 per cent a. i. on bud break and other growth parameters. The experiment was conducted at Indian Institute of Horticultural Research, Hessaraghatta, Bangalore, India during 1991-92. The results revealed (Table I) that all the sixteen treated genotypes exhibited increased budbreak compared to the untreated genotypes. The genotype, Qyexhibited highest increased budbreak to the tune of 140.74 per cent over control. In contrast to this, a minor increase (8.53 %) over control was shown by the genotype, E-29/6. The process of budbreak was relatively uniform in the genotyes, E-14/20 andE-21/28 in which budreak was completed in 5 and 5.33 days, respectively.