Early precocity and productivity of cherry varieties in the conditions of the North-Western Caspian region

On the territory of the garden of the Federal State Budget Scientific Institution Caspian Agrarian Federal Scientific Center of the Russian Academy of Sciences, a variety study and selection of promising cherry varieties that are most adapted to the arid conditions of the Astrakhan Region are carried out. The paper presents the results of the first stage of the study of introduced cherry varieties of domestic selection: Pamyati Zhukova, Korneevskaya, Turgenevskaya, Izobilnaya, grafted onto a medium-sized rootstock VTS-13. Precocity is the most important quality of perennial fruit plants, which determines the beginning of the entry into the fruiting period. Increasing the production of high-quality cherry fruits is the main task of industrial production, so the cultivation of cherry varieties, characterized by early maturity and high yield, is of great importance. The results of the study of the entry of cherry varieties into the fruiting period and the assessment of the quality of the fruits are given. The conducted studies have revealed differences in the precocity and productivity of the studied cherry varieties. According to the results of research, the variety of cherries Pamyati Zhukova is considered the most early-growing, the laying of fruit buds was observed already in the second year of planting in the garden. Late entry into the fruiting period, on the 4th year of planting, was noted in the varieties Izobilnaya and Korneevskaya. Tree productivity is a set of biological characteristics of a variety that determine resistance to biotic and abiotic stress factors during the growing season, stability of fruiting and fruit quality. The productivity of stone fruit crops is negatively affected by spring return frosts, which are often observed in the North-Western Caspian Region. During the study period, frosts were observed with an air temperature at night of -5...-7 °С. In 2019 and 2021, the air temperature dropped to -5 °C, in 2020 - to -7 °C. In all cherry trees in the budding phase, freezing of buds was observed, which negatively affected the fruiting strength of fruit plantations, the productivity of cherry varieties was 0.1-2.7 kg/tree. No return frosts were observed in 2022, which significantly increased tree productivity to 3.0-15.7 kg/tree. The most productive variety is the Pamyati Zhukova - 15.7 kg/tree. According to the years of research, the varieties Pamyati Zhukova (5.6-8.0 g), Turgenevskaya (4.5-5.7 g) and Korneevskaya (5.0-6.7 g) were distinguished by large-fruitedness. Small fruits were observed in the Izobilnaya variety - 3.7-3.8 g. The tasting score of the varieties was 4.5 points.