Relationship Between Bud Cold Hardiness and Budbreak in Two Vitis vinifera L Cultivars, Chardonnay and Thompson Seedless

Abstract The lack of winter cold is a severe limitation for the cultivation grapevines ( Vitis vinifera L) in areas with warm climates. This phenomenon currently becoming quite important due to global warming, which will increase temperatures many temperate regions planet where are cultivated. Although various physical and chemical stimuli have been used address grapevine cultivation, quantitative studies on its effects different cultivars limited. Here, (a) low during endodormancy (ED), (b) temperature increases eco-dormancy (ECD) (c) dormancy-breaking compounds such as hydrogen cyanamide (HC) sodium azide (AZ) budburst an early budbreak cultivar, Chardonnay, late Thompson seedless, were assessed. results analysed by Kaplan–Meier method, log-rank test was establish statistical significance between control treatments. In general, Chardonnay more sensitive than seedless all stimuli, ECD stimulus that had greatest effect both cultivars. Exposure ED increased hardiness improved Based results, relationship degree bud potential suggested, it proposed greater achieved buds, better their subsequent be.