WINTER HARDINESS OF CLONAL APPLE ROOTSTOCKS IN THE SOUTHERN BAIKAL REGION

The article presents the results of a study of clonal rootstocks of apple trees of different geographical origins, conducted in 2017-2024 on experimental plots located in the Irkutsk region. The object of study is clonal rootstocks are six varieties bred by Michurinsky State Agrarian University (62-396, 54-118, 70-20-20, 70-6-8, 64-143, 62-223), a rootstock bred by A.P. Apoyan (Armenian Research Institute of Viticulture, Winemaking and Fruit Growing) - Arm18, Estonian - E56, seven Orenburg experimental station of horticulture and viticulture (Ural, Ural2, Ural5, 18-7, OB-3-4, 4-12, 8-2) and the Crimean experimental and selection station of VIR (K-2). The environmental conditions of the Southern Baikal region are favorable for the use of clonal rootstocks in regional horticulture. It was found that the most adaptive forms of all the samples are those of the Ural selection (Ural and Ural 2) and Estonian (E56). E56 survived the winter best, 70-6-8, Arm18 and K-2 did worse, the rest showed average winter hardiness. Differences in the presence of dehydrin proteins in the bark of rootstocks with differet winter hardiness depending on the month were found. In our experiments, the major dehydrin was a protein with a molecular weight of 45 kDa.