The uvological reaction of the Pamyati Uchitelya table grape variety to a decrease in the number of shoots on bushes in conditions of increased solar insolation

Abstract. The work is devoted to the study of the reaction of plants according to the degree of change in the biometric values of bunches and grapes to extreme weather conditions of the moderate continental climate of the south of Russia and the normalization of the load of bushes with shoots. The research was carried out in the Central agroecological zone of the viticulture (subzone № 4) of the Krasnodar region on the fruitbearing vineyards of the table grape variety in Pamyati Uchitelya (Talisman × Kardinal). The scheme of planting bushes is 3.5 × 3.5 m, the culture is covered with drip irrigation. The scheme of the field experiment includes three options for loading bushes with shoots: 1. Control without changing the number of shoots on bushes; 2. Reducing the number of shoots on bushes by 20 %; 3. Reducing the number of shoots on bushes by 40 %. The formation of grapes took place in conditions of increased insolation and an acute shortage of precipitation. Under these conditions, the variety retained attractive dimensional characteristics of grapes and grapes. The bunch weight remained large on average 465 g, the weight of the berry – 5.1 g. The variety reacts very sensitively to changes in the number of shoots on grape bushes. With a decrease in the number of shoots by 20 and 40 %, the bunch weight increases by 10 and 54 %, respectively, to 513 and 715 g relative to the control variant (465 g). The weight of the berries at the same time had an inverse dependence on the number of shoots and decreased by 24 and 12%, to 3.9 and 4.5 g compared with the control variant (5.1 g). In a moderate continental climate in the Central agroecological zone of viticulture of the Krasnodar region, in order to obtain a large attractive bunch without significantly reducing the size of the grapes of the Pamyati Uchitelya variety, it is recommended to reduce the number of shoots by 40 % relative to the load of bushes used in production conditions. Keywords: Increased insolation, precipitation deficiency, grapes, shoots, bunch, berry