Fruit growing
and viticulture of South Russia

Annotation

Winter hardiness of fruit plants must be regarded as genetically determined property, the implementation of which depends on the physiological state of trees in the process of cultivation, and also from photosynthetic activity of leaves. The development of frost resistance and the loss of this property is significantly associated with changes of water state in the fruit plants tissues. For assessment of changes in water balance are increasingly using a differential thermal analysis (DTA) of ice formation processes in the organs and tissues of plants. The aim of our work is to analyse a number of cherry cultivars for winter hardiness using the DTA meth-od providing for the thermal analysis of ice formation in the tissues of studied plants. The objects of our study were one-year shoots and buds on the trees of 10 cherry cultivars in the orchards of 1997 planting. Definition of exothermic processes in the shoots of cherry trees with generative buds was carried out in the different periods of winter. The data obtained of the analysis of ice formation by thermographic method allowed to clearly identify the features of heat dissipation in the shoot's tissues of cherry cultivars with different frost resistance. It is noted, when the plants are going from dormancy, there are changes of water and physical parameters of the tissues, accompanied by a deepening of the front of ice formation in the most varieties at 1-6 �C. The carried out comprehensive analysis al-lowed us to divide the studied cherry varieties into groups for winter hardiness: highly resistant varieties are the Alpha and the Turgenevka, the varieties with intermediate resistance � Radost, Favorit, Nochka, North Star, Podbelskaya, and varieties with low winter hardiness � Rebetskaya Krasavitsa, Donetskiy Velican and Chudo-Vishnia.