| Abstrakt: |
Abstract: In the years 1963-1965 the content of proline, asparagine, glutamic and γ-aminobutyric acids in young apple (Malus cultivars) shoots was studied. Two groups of apple varieties differing in frost resistance were included into experiments: the Yellow Transparent and Oberländer Himbeerapfel varieties as frost-resistant ones and-the Ontario and Reinette du Canada varieties as sensitive to frost. In the course of experiment γ-aminobutyric acid showed a relatively balanced level but glutamic acid, asparagine and especially proline were found in greater amount in the frost-resistant varieties. According to the results of this experiment the amount of proline-along with many other factors-can be considered as one of the indicators of the length of winter dormancy and also of the frost resistance of apple-trees at the beginning of the winter period. |
