Note on effect of thiourea on breaking of dormancy of grapevine buds

摘要

There are limitations in the extension of grape culture in northern India because of the various biological peculiarities of grapevine, which it possesses owing to its evolution in the temperate latitude. Temperate climate is characterized by a hot and almost rainless summer, followed by rains and severe winters. The vines under such conditions grow and fruit during summers and enter into complete dormancy during winters. In contrast to this, the climate of northern India greatly differs in the sense that monsoon sets in by the middle of June when the crop begins to ripe and these early rains cause considerable damage to the grapes at ripening stage. Under natural agro-climatic conditions of Meerut region of north-India, grapevines sprout in late February to early March and the fruits mature by the second to third week of June. Onset of monsoon rains by the middle of June do not permit complete ripening of the bulk of the crop. Hence, it is necessary to protect the crop from spoilage by rains and bring it to full maturity before the onset of monsoon. Thiourea has been successfully used for breaking the dormancy of buds in peach (Fernandez-Escobar and Martin, 4; Erez et al., 3). Tile present study deals with the effect of thiourea on breaking the dormancy of grapevine buds of cv. Bhokri to advance the maturity of the crop.