Effects Of Drought Stress On Photosynthetic Properties And Microscopic Structure Of The Leaves Of Cabernet Sauvignon

Two years of the European cultivar grapevine (Cabernet Sauvignon) were planted in the plastic pots under the glasshouse environment, which were studied in different gradient drought stress and rehabilitation of water, its photosynthetic physiology, photosynthetic pigment content, as well as indicators of shape Microscopic changes in the structure of leaves.The purposes of this study were the following findings:1. Effects of drought stress on the form of indicators of Cabernet Sauvignon Under drought stress, grape plant height, section spacing, diameter, shoot dry weight, the ground floor of the dry weight of the form, and other important indicators have significantly decreased, which fully shows that drought stress can significantly reduce the plant biomass, and the greater the level of stress, the greater the impact on the plant. Stress after rehabilitation treatment, plant height, section spacing, diameter, shoot dry weight, the ground floor of the dry weight form indicators have increased, the lower the degree of drought stress, the stronger its recovery capacity, but are lower than the control plants.2. Effects of drought stress on the photosynthetic characteristics of Cabernet Sauvignon Along with the deepening drought stress level, the net photosynthetic rate (Pn), Conductance to H2O (Gs) and transpiration rate (Tr) were significantly lower, the intercellular CO2 concentration (Ci) first but eventually reducing the cumulative increase, Grape photosynthesis capacity increase with the degree of stress and decline; Rehydration after Pn, Gs, Ci, Tr with the increase in soil moisture and gradually restored, but the parameters are not restored to pre-stress levels.3. Effects of drought stress on the photosynthetic pigments of Cabernet Sauvignon In mild drought stress, grape photosynthetic pigment content increased significantly, with the increased level of stress, pigment content beginning to show a downward trend, and the greater the level of stress, the lower the content of photosynthetic pigments. After rehabilitation treatment, leaf pigment content has rebounded, with the exception of mild drought stress, moderate stress and serious stress after the plant photosynthetic pigment content was lower than the control.4. Effects of drought stress on the microscopic structure of the leaves of Cabernet SauvignonDifferent gradient of drought stress, grape leaves on the surface of the waxy increased thickening of the stratum corneum, fencing, and vascular bundle sheath become developed and a series of changes. Stomata opening of the vision unit volume decreased significantly, the opening of stomata correspondingly decreased. Stomata from the beginning of the convex gradually subside. Dehydrations after stomatal size did not change significantly, but some can stomatal closure by the state to open the state.