**4. Conclusion**

Summarizing the above, it can be approved that the problem of drought resistance and heat resistance of varieties is currently particularly acute. The increase of variety stability now gets the great relevance, since the numerous experiments prove that only the use of the adapted varieties and the transition to adaptive, biological, and low-cost technologies of cultivation of fruit-growing production are possible [67]. Many issues related to the peculiarities of the water regime and physiological and biochemical processes remain unclear. In our work we have shown that berry crops, including red currants, have complex and little-known mechanisms of adaptation to drought and abnormally high temperatures. The prospects of using physiological methods in assessing the resistance of *Ribesia* (Berl.) Jancz samples to adverse weather factors have been proved. The obtained results were fully confirmed by field observations of stability of red currant varieties and selected forms under conditions of high temperature and moisture deficit. This makes it possible to use the considered methods as a rapid diagnostics and significantly intensify the selection for adaptability. As shown by the complex physiological assessment, the derivatives of different species of the *Ribesia* (Berl.) Jancz subgenus have a different ecological plasticity, which is explained by the difference of their genetic and ecological-geographical origins. The derivatives of different species of the *Ribes petraeum* Wulf. ("Hollandische Rote") and *R. muliflorum* Kit. (1426-21-80) showed the greatest resistance to dry conditions of the vegetation period in the Central Chernozem Region that gives reason to use them in introduction. Low drought resistance was observed in the varieties and selected forms of *Ribes vulgare* Lam.
