Tatyana Yanchyk

Water regime dynamics of the Imrus apple cultivar grown on dwarf and semi dwarf intermediate stocks was studied during vegetation. As a result of the investigations the highest total water contents of the variety-rootstock combinations was noted at the beginning of vegetation and then, as the age of leaves increased and the water-supply-level of plants decreased, the contents of the total and available water were reduced. The increase of bound water was observed during more droughty periods. As a result of leaf water loss and the following water saturation, Imrus grown on small-sized intermediate stocks showed the moderate level of drought resistance.

Stone fruit crops are successfully cultivated in many regions of Russia. Their fruits contain a great diversity of biologically active and mineral substances. The stone fruit varietal collection of the All Russia Research Institute of Fruit Crop Breeding has been estimated on the content of biologically active substances (ascorbic acid and phenolic compounds) in fruits: 80 sour cherry varieties, 28 sweet cherry varieties, 29 plum varieties and 24 apricot varieties. High cultivar variability of the content of ascorbic acid and P-active sub-stances in fruits has been determined in each crop. The best genotypes have been singled out according to each biochemical component and a complex of characters.