Evaluation some of the physiological and biochemical changes in three grapevine cultivars (Vitis vinifera L.) in response to drought stress

In this study evaluate the effects of grapes cultivar on tolerance of vitis vinifera grown in drought stress conditions. Plants were grown in pots and exposed to 0, 40, 60 and 80 percent of fild capacity drought stress with three different cultivars (perlet, khaliliand ghizil ouzum). The physiological parameters such as MDA, H2O,EC and morphological paramaters such as dry and fresh weight and chlorophyll fluorescence Fo,Fv, Fm, Fv/Fm, Y(II) Y(NO) the contents of chlorophyll a, chlorophyll b, and enzyme activities of (APX, GPX, and CAT) and prolin content and protein percent were determined. Grapes cultivars positively (ghizil ouzum) affected on growth and physiology statistically. The highest, proline content was significantly different under drought stress condition and ghizil ouzum treatments so that, enzyme activities of (APX, GPX, and CAT) are increased with enhancement of drought levels .interaction effects of drought and cultivars in CAT, APX and GPX activity were significantly different compared with control and increased with enhancement of stress levels so that most of the activity was in 60% fc concentration and ghizil ouzum cultivar. The amount of chlorophyll fluorescence parameters (Fm, and Fv, Fv/Fm, Yll, Y(N0) were significant changes in drought stress treatment and ghizil ouzum in 60% FC compared with control.