Preliminary Study On Drought Resistance Of 10 Table Grape Cultivars In Xinjiang

Xinjiang is one of the regions with extremely scarce water resources in China,so drought has become the main factor restricting the healthy development of grape industry in Xinjiang.The main table cultivars‘Flame Seedless’and‘Summer Black’in Xinjiang and the new introduced grape cultivars‘Crimson Rose’‘Wagamichi’‘Silk Road Red Rose’‘Shine Muscat’‘Blackcrunchy Seedless’‘Hutai No.8’‘Zitian Seedless’and‘Sweet Sapphire’were selected as the research objects.Adopted to a water control in pot culture method to simulate drought stress,to observe the morphological characteristics,microstructure,diurnal changes of photosynthesis and chlorophyll fluorescence,and changes of physiological and biochemical indexes of each table grape cultivars and combined with principal component analysis,membership function method and cluster analysis,the drought resistance of 10 table grape cultivars were ranked and classified.It was expected to provide scientific and technological support for further promotion of table grape cultivars in arid areas.The results were as follows:（1）By observing the leaf anatomical structure of 10 table grape cultivars under drought stress,it was found that the sensitivity of P/S to drought stress was the highest.The order of drought resistance of 10 table grape cultivars calculated by principal component analysis was:‘Blackcrunchy Seedless’>‘Shine Muscat’>‘Crimson Rose’>‘Flame Seedless’>‘Hutai NO.8’>‘Summer Black’>‘Wagamichi’>‘Zitian Seedless’>‘Silk Road Red Rose’>‘Sweet Sapphire’.（2）The diurnal variation of photosynthesis of 10 table grape cultivars under drought stress was observed.During the day,under sufficient water supply,the net photosynthetic rate,transpiration rate and stomatal conductance of 10 table grape cultivars showed obvious“double peak”curves.Diurnal variation of intercellular CO₂concentration showed an“U”shaped curve that first decreased and then stabilized and finally increased,The results of principal component analysis showed that the drought resistance ability of table grape cultivars was:‘Blackcrunchy Seedless’>‘Shine Muscat’>‘Crimson Rose’>‘Flame Seedless’>‘Hutai NO.8’>‘Summer Black’>‘Wagamichi’>‘Silk Road Red Rose’>‘Sweet Sapphire’>‘Zitian Seedless’.（3）The diurnal variation of chlorophyll fluorescence of 10 table grape cultivars under drought stress was observed.During the day,the variation curves of Fm,Fv/Fm andΦ_PSIIall fell frist and then rose,the variation curves of Fo and NPQ rose first and then fell.The results of principal component analysis showed that the order of drought resistance ability of 10 table grape cultivars was:‘Blackcrunchy Seedless’>‘Shine Muscat’>‘Crimson Rose’>‘Hutai NO.8’>‘Flame Seedless’>‘Summer Black’>‘Silk Road Red Rose’>‘Wagamichi’>‘Sweet Sapphire’>‘Zitian Seedless’.（4）Through observation found that with the deepening of drought stress,the root activity of the 10 table grape cultivars were decreased,the relative conductivity,proline content and peroxidase activity of leaves and roots were increased,while the proline content,peroxidase activity and superoxide dismutase activity of leaves and roots rose first and then fell.Further through principal component analysis,the order of drought resistance of grape cultivars was:‘Blackcrunchy Seedless’>‘Shine Muscat’>‘Crimson Rose’>‘Hutai NO.8’>‘Flame Seedless’>‘Summer Black’>‘Silk Road Red Rose’>‘Wagamichi’>‘Sweet Sapphire’>‘Zitian Seedless’.（5）Combined with the above changes in various indicators,the use of cluster analysis and evaluation.According to the drought resistance,10 table grape cultivars were divided into three categories:‘Blackcrunchy Seedless’and‘Shine Muscat’have stronger drought resistance;‘Crimson Rose’‘Flame Seedless’‘Hutai No.8’‘Summer Black’and‘Silk Road Red Rose’have moderate drought resistance;‘Wagamichi’‘Sweet Sapphire’and‘Zitian Seedless’have weak drought resistance.