Mizyak A. The influence of leaf phylloxera on productivity of grapevine

The complex nature of the injuriousness of the leaf form of phylloxera has been proved. At the gall formation intensity of 11% and higher, the reductions have been established for the first time in the number of buds that already broke and fruit buds - by 10-14%, in the number of flower clusters - by 15-18%, in the per shoot leaf number - by 4-5%, in the per shoot leaf area - by 20-37%, in the total leaf area in the per cluster, per shoot and per vine - 1,9, 1,7 and 1,7 times, respectively, in the cane productivity - 1,1-1,2 times and in the sugar content of the cluster - 1,2-1,3 times. The technical efficiency and the optimum terms of application of the insecticide preparations Confidore, Mospilan, Talstar, Nurel D and Bi-58 N have been established, the technical effectiveness being 77,7%-94,3% over the period of industrial ripeness. An improved and economically effective system of chemical protection against the leaf form of phylloxera taking account of grape moth development has been elaborated. The profitability of grape production relative to the control increases by 10,5-13,6%.