Grapevine Carbernet Sauvignon’s Changes Of Physiology And Biochemistry After Mildew Downy Infection

With3strains of wine grapes in a filed disease investigation, the results showthat Dragon violet pearl is highly resist on downy mildew, during the whole diseaseepidemic season, it doesn’t onset. There’s a difference of disease index and theincidence of disease between Cabernet Sauvignon and Yan-73. Cabernet Sauvignon’sresistance of downy is the worst of all, the disease index and the incidence of diseaseis the highest during the whole disease epidemic season.With comparison of Cabernet Sauvignon’s leaves’ physiological andbiochemical indexes under the condition of normal and inoculation, The results showthat with the disease severity aggravated gradually, Cabernet Sauvignon’s activity ofSOD and POD, plasma membrane permeability and the intercellular CO2concentration show a increase trend, but the net photosynthetic rate, transpiration rate,stomatal conductance, the leaf relative water content and the total content ofchlorophyll show a decrease trend; Meanwhile, across to the study of differentconcentrations of Calcium treat soilless cultivation Cabernet Sauvignon’s leavesunder the disease stress’s effects on plasma membrane, photosynthetic parameters, theactivity of SOD and POD. The results show that under the disease stress, exogenouscalcium can keep the activity of enzymes in some degree, enhance the photosyntheticrate, decrease the plasma membrane permeability, in order to improve the diseaseresistance. The best general treatment concentration of Ca(NO3) is23.75g／L.