Grape is one of the most important horticultural products and for suitable growth in spring, it must chilling requirement be provided.Determination of the amount of chilling requirement in fruit trees because carefully cultivated varieties adapted to different regions in order to buds flourishing and prevent frostbite as well as produce more product is essential. This research work was conducted to determination of the amount of chilling requirement in ‘Khalili’, ‘Syah Gerdel’ and ‘Atabake’ grapevines. Dormant cuttings grape from collection grape of maternal plants of university of Tehran was prepared at the onset of autumn. The cuttings were taken to fridge at 3 ± 1ºC in dark conditions. The cuttings were taken kept in growth chambers at 25 ± 2ºC under a Full-light conditions. Then twice a week, the buds burst was evaluated that number of buds flourishing and date of bloom was recorded. Results showed that the use of cold treatment and type cultivar had a significant effect on percentage of buds flourishing and time period of first bud burst. Based on results, the lowest percentage of buds flourishing (%22.2) and the highest number of days to first bud burst (%32.16) was obtained by control treatment. Evaluation of flowering buds showed that lowest chilling requirement and higher percentage of buds flourishing among cultivars belonging to cultivars ‘Syah Gerdel’ with 150 hours of chilling requirement and ‘Atabaki’(%74.78), respectively. The results of this research showed that the usage of cultivar ‘Syah Gerdel’ than the other two cultivars is efficiently in areas with warm or mild winter. According to the results, in the range of chilling time, at least 200 hours of chilling to achieve acceptable bud burst and high production in ‘Khalili’, ‘Syah Gerdel’ and ‘Atabaki’ cultivars, is necessary.
