Effects Of Different Leaf To Fruit Ratio Treatments On Organic Acid Accumulation And Berry Quality Of "Cabernet Sauvignon" And "Bei Mei" Grape Before Veraison Stage

In order to improve the quality of wine grape,study the effects of different leaf to fruit ratio on growth and development,organic acid accumulation and berry quality.The 6 years old "Cabernet Sauvignon" and 3 years old "BeiMei" were used as experimental materials in this experiment,by the way of reducing leaves and reducing fruit to adjust the leaf to fruit ratio treatments were performed before the veraison stage.The growth and development,the content of organic acids,sugars,tannins,total phenols and anthocyanin content of grape wine were observed and compared during wine grape fruits growth.The results show that:1.The 100-seed weight shows an increasing trend with the increase of leaf to fruit ratio.The 16:1(leaf/cluster)treatment of "Cabernet Sauvignon" and "BeiMei" wine grape got the maximum 100-seed weight.However,compared with the control groups,it had not obvious change of 100-send weight among different treatment groups.2.Different leaf to fruit ratio treatment.The content of malic acid and citric acid in grape wine increased with the decrease of leaf to fruit ratio,while the content of tartaric acid increased with the increase of leaf to fruit ratio.The content of malic acid and citric acid in "Cabernet Sauvignon" and"BeiMei" grape fruits increased significantly when the leaf to fruit ratio was less than 16:1(leaf/cluster)If the leaf to fruit ratio greater than or equal to 16:1(leaf/cluster),tartaric acid would be accumulated in grape fruits.3.Wine grapes at harvest time,When the leaf to fruit ratio of "Cabernet Sauvignon" and "BeiMei"grape were 16:l(leaf/cluster),the total soluble sugar,reducing sugar,total phenols,tannin and total anthocyanin content in grape fruits increased obviously.At the same time,the titratable acid content was moderate in the fruit of "Cabernet Sauvignon" and "BeiMei" The quality of wine grape was improved obviously.Therefore,according to the above results,the type of organic acids' accumulation in grape fruits was different under various treatments of leaf to fruit ratio.At the same time,increased the leaf to fruit ratio could improve the quality of wine grape within a reasonable range of leaf to fruit ratio.Under the conditions of this experiment,it is suggested that the optimum leaf to fruit ratio of "Cabernet Sauvignon" and "BeiMei" in east of the Helan mountain is 16/1(leaf/cluster).