Characteristic features of cracking of sweet cherry fruit surface

Sweet cherry fruit сracking during the rain has significant economic consequences. The level of cracking can reach as much as 100 % of losses, making the harvest unfit for sale. By understanding the cause of the damage, growers will be able to produce crops of quality cherry fruit. The development of varieties highly resistant to cracking is the main objective of most breeding programs. The article presents the research results on sweet cherry fruit cracking of the varieties of various ripening periods. In the study, fruits of 12 varieties of domestic cherry selection were used. Fruits at shoot ripeness were placed in containers with distilled water and kept for a certain period of time. After 6, 12, and 24 hours of exposure, cracked fruits were identified and the characteristic crack damage for each variety was determined. On fruits with cracked peel, the type of damage was determined, conditionally divided into: at the pedicel, on the side and around the top of the fruit. As a result of observations of cracking of cherry fruits, it was possible to determine the peculiarities of damage of each variety. Types A and B damage is shallow and may heal before the fruit is fully ripe, while C-type damage is deep, often down to the seed, which causes fruit rotting. Observations revealed that early maturing varieties were characterized by lateral cracking. These were tentatively divided into cracks near the peduncle, on the side, and around the top of the fruit. The observations made it possible to establish that early ripening varieties had the cracking on the side of the fruit. Fruits of medium-ripening varieties cracked mainly around the top of the fruit. Late-ripening varieties were equally characterized by cracking at the peduncle and around the fruit top. The correlation analysis of the influence of some biological components of the fruit on peel resistance to cracking was carried out. As a general result, among the studied varieties of different ripening dates, it can be stated that the most resistant to cracking were fruits of varieties «Mlievskaya yellow», «Mirazh», «Meotida» and «Amazonka». Key words: sweet cherry, resistance to cracking, nature of fruit surface damage, peduncle length, pit mass fraction.