The reaction norm of Augustine and Moldova grape varieties in the agroecological conditions of the moderate continental climate of the south of Russia

Federal State Budget Scientific Institution «North Caucasian Federal Scientific Center of Horticulture, Viticulture, Wine-making», str. 40 Let Pobedy, 39, Krasnodar, 350901, Russia

^* Corresponding author: petrov_53@mail.ru

Abstract

The grape plant reacts by modification variability of phenotypic traits to the variation of weather conditions. The reaction of the Augustine and Moldova grape varieties to the variability of natural conditions was ambiguous. In the Augustine, the lower limit of the modification variability of the cluster mass is 354 and the upper limit is 410 g, the grape yield is 8.1 and 11.5 kg/bush, the sugar content of the berry juice is 15.8 and 17.5 g/100 cm³, in the Moldova, respectively, 387 and 457 g, 9.6 and 13.2 kg/bush, 16.4 and 17.8 g/100 cm³. The reaction norm of the Augustine according to the phenotypic traits is following: the cluster mass is 56 g, the yield is 3.4 kg/bush and the sugar content is 1.7 g/100 cm³, of the Moldova, respectively, 70, 3.6 and 1.4. Against the background of the application of fertilizers, the lower and upper limits of variability have increased as well as the reaction norm by cluster mass and yield, however reaction norm by sugar content decreased.