The Research Of Characteristic And Physiological Mechanism On Grapes Under Drought And Cold Stress

Two table grape cultivars Jingya and Red Glob, two wine grape cultivars (Cabernet Sauvignon and Merlot) and eight grape rootstocks were selected in the experiment. In drought condition, the branch and root growth, leaf photosynthesis and physiological and biochemical indexes of grape were determined. The branch and root of grape were exposed to different low temperature, and the cell membrane permeability was determined. The main results were as follows:1. Under drought stress, there was close relationship between the drought resistance of tested grape cultivars and their branch growth, as well as root growth. With the deepening of drought stress, the growth of branches and roots was reduced.2. With the deepening of drought stress, the relative water content, chlorophyll content and soluble sugar content in the strong drought resistance of grape cultivars leaves were higher than that of the weak drought resistance of grape cultivars. However, MAD had negatively for the grape hardiness in the leaves. Also the cell membrane permeability of the strong drought resistance grape cultivars were more stability than the weak drought resistance cultivars.3. When drought stress became worse, the SOD and POD activity of different grape leaves were showed a rising trend. The SOD activity was rise amplitude and slow down in the grape cultivars of strong drought resistance; the higher the POD activity increased in the leaves of different grape cultivars, the stronger the grape cultivars of drought resistance.4. In the condition of drought stress, Pn and Cond increased at first, after that it reduced as the drought stress processing in different grape cultivars. The Tr in the leaf gradually reduced as the drought stress processing. However, the Ci in the leaf reduced at first, after that it increased as the drought stress processing.5. In the condition of low temperature, the hardiness of grape cultivars of different branches was affected on the water content and maturity of branch. The higher the maturity of the grape shoots was, the stronger the hardiness of grape branches was. And, the higher the water content of branches, the stronger the hardiness of grape cultivars.6. In the condition of low temperature, the relative conductivity of the branches and roots significantly increased, but there had a certain differences in different species on different temperature rises. Along with the processing temperature lower, damage degree was increased. The relative electric conductivity of branches was more and more big, and was a growing trend. Showing the low temperature treatment that made the damage rate of cell membrane increased. Research found that the conductivity of twelve grapes with the processing temperature dropping, present slow-fast-slow increase trend, and present the S curve.7. Through researching the physiological indexes of the grape cultivars, the sequence of drought resistance of the grape cultivars from strong to weak was: Jingya>Jingya grafted seeding>Red Glob>Red Glob grafted seeding; The sequence of cold resistance of branch was:Beta>1103P>SO4>5C>110R>5BB>520A>140R>Red Glob>Merlot>Jingya>Cabernet Sauvignon:The sequence of cold resistance of root was: Beta>5C>1103P>520A>5BB>S04>110R>140R.