Winter-hardiness and frost resistance of clones of an apple (Malus domestica Borkh.) of the grade Jonagold of domestic selection

Abstract

The purpose. To determine extent of winter-hardiness and frost resistance of 20 clones of an apple of the grade Jonagold in conditions of Podillia. Methods. Field (determined extent of winter-hardiness of trees of clones), laboratory (test exposition of plant material to frost), comparative, generalizations. Statistical analysis of results of frost resistance was spent with application of the method of system of quotients. Results. In zone of Western Forest-steppe they selected clones with high level of winterhardiness and frost resistance. Conclusions. According to probes trees of clones DP-9, DP-11, DP-17, DP-18, DP-19, DP-20 had the higher extent of winter-hardiness (8,5 — 8,8 points). Plants of clones DP-2, DP-5, DP-9, DP-10 and DP-15 were characterized by high potential of frost resistance (2% of damage).