Study of frost resistance and drought resistance of apple tree varieties of VNIISPK breeding on clonal rootstock 54–118

Apple tree varieties on clonal rootstock 54–118 were studied in terms of frost resistance and drought resistance. The purpose of the research is to study the resistance to frost and drought of apple tree varieties of VNIISPK breeding on clonal rootstock 54–118. Climatic conditions affect fruit trees and further lead to a sharp decrease in the fruit productivity and commercial qualities. The problem study of resistance to various extreme growing conditions (including frost, low temperatures, drought and high temperatures) is relevant. A variety that has a high resistance under various adverse weather conditions is considered as winter-hardy, i.e. shows all the components of frost resistance. The study of the main components of winter hardiness (I, III, IV) showed that apple tree varieties (Orlik, Venyaminovskoye, Sinap Orlovsky, Veteran, Svezhest, Rozhdestvenskoye, Bolotovskoye - of the FSBSI VNIISPK breeding; Antonovka obyknovennaya - of local selection on clonal rootstock 54–118) had minor bud damage. The bark and wood were not damaged. When studying the total water content of leaf tissues during the growing season, all varieties on the clonal rootstock 54–118 were assigned to the average level of hydration. In laboratory conditions, over the years of research, the varieties had a high indicator of the ability to restore water content of leaf tissues after drought. On the clonal rootstock 54–118 the apple tree varieties are able to withstand thaws, spring frosts, droughts and dry winds.