DROUGHT AND HEAT RESISTANCE OF ROOTSTOCK-SCION COMBINATIONS

Research was carried out on the basis of the Uchkhoz KNAU in order to identify the influence of clan rootstocks on the yield of standard apple tree seedlings. The objects of research were bug rootstocks of apple trees MM 106, M26, M9, ARM18, ZHETYSU 5. The apple tree varieties Golden Delicious, Kandil Sinap, Rashida, Renet Burchardt and Kirgizskoye Zimneye were tested as scions. Kyrgyz winter variety, author E.Z. Garev, bred in the Botanical Garden of NAL of Kyrgyzstan from crossing the Aport and King David varieties, late winter ripening. The trees are vigorous, the variety begins to bear fruit in the sixth year, bears fruit annually, and the yield is high. The trees are vigorous, the variety begins to bear fruit in the sixth year, bears fruit annually, and the yield is high. Resistant to powdery mildew. Branches with a medium angle of branching, shoots brown, medium pubescent. A variety with a mixed type of fruiting, begins to bear fruit early, and is productive. The Rashida variety was obtained in the Botanical Garden of the National Academy of Sciences of Kyrgyzstan from crossing the varieties Aport Alexander x Jonathan, author E.Z. Gareev. The tree has a spreading crown. Kandil-sinap from the group of sinaps, autumn ripening period. The origin of the variety is unknown; according to the most common version, it was obtained by random mutation when sowing seeds of a related variety, Sary-sinap. The Golden Delicious variety was the result of an unintentional cross. The varieties Grimes Golden and Golden Reinette are usually indicated as probable parents. The lack of moisture was annually felt in the summer months, especially in July, when thermal stress reached its maximum values. During this period, a large amount of water evaporates into the soil, is spent on formation and transpiration activities. After studying the drought resistance and heat resistance of rootstock-scion combinations in 2021. over the next three years, the parameters of the water regime of rootstock-scion combinations were analyzed - water content of leaves, water-holding capacity, water deficit, and restoration of water content in order to assess their resistance to summer stress