The Preliminary Study On Resistance Mechanism OfVitis Davidii Foex To Downy Mildew And Botrytis Cinerea

This test used Vitis davidii Foex NO.1, NO.2, NO.3, NO.4as material, Hutai No.8, Red globe, Ruby Seedless and V.adenoclada Hand.-Mazz as contraposition, studied the Resistance Mechanism of Vitis davidii Foex to downy mildew and botrytis cinerea by identifying resistance through Indoor and field inoculation and measuring. The content of related antiviral substances and structural features for grape leaves, intending to provide a reference for the breeding, cultivation of Vitis. The results show that:1. The four types of Vitis davidii Foex are resistant to botrytis cinerea. Vitis davidii Foex NO.1is susceptible and NO.2, NO.3, NO.4are medium susceptible to downy mildew. Hutai No.8is medium susceptible to downy mildew and Ruby Seedless and Red globe are medium susceptible to botrytis cinerea and moderate resistance to downy mildew. V.adenoclada Hand.-Mazz is resistant to both two diseases.2. Wax content of leaf epidermis in Vitis davidii Foex is positively correlated with disease resistance, and the stomatal density of blade back is correlated negatively with disease resistance. The stomatal density of Vitis davidii Foex NO.1, NO.2, NO.3, NO.4decreased systematically, and the wax content of leaves increased.3. The amount of increase for PPO and POD activity in the leaves of Vitis davidii Foex had positive relative with disease resistance post inoculation. For the activity of PPO and POD were increased by inoculation with botrytis cinerea, and decreased with downy mildew, so the resistance to botrytis cinerea of Vitis davidii Foex is good and to downy mildew is poor.4. The leaves of Vitis davidii Foex have the highest content of tannin between, secondly for Hutai No.8. The fruits of V.adenoclada Hand.-Mazz have the highest content of tannin, secondly for Vitis davidii Foex. Combining the evaluation result of resistance, the content of tannin in different kinds of grapes has no positive relative with disease resistance. However, between four types of Vitis davidii Foex, NO.2, NO.3and NO.4have higher content of tannin and better disease resistance, so, the content of tannin in leaves between is positively correlated with disease resistance.5. Since the types of Vitis davidii Foex with higher content of Lignin have better resistance, the content of Lignin in Vitis davidii Foex leaves is positively correlated with disease. But they are not positively correlated in different kinds of grapes.6. The content of soluble sugar in leaves and fruits has negative correlation with resistance to botrytis cinerea and no correlation with resistance to downy mildew. The leaves of V.adenoclada Hand.-Mazz which has the highest resistance to botrytis cinerea have the highest content of soluble sugar, secondly for Vitis davidii Foex. The content of titratable acid in fruits has positive correlation with resistance to botrytis cinerea and no correlation with resistance to downy mildew.