不同时期苹果花芽和叶芽中内源赤霉素脱落酸和细胞分裂素活性的变化

 本文为了探讨苹果花芽分化与内源激素的活性变化关系，改变了以往测定短枝混合样本（含花芽和叶芽）的传统作法，而采用花芽和叶芽分开测定的研究方法，取得了较好的效果。结果表明，所测内源GA#-3、CTK和ABA等激素在花芽分化过程中均存在。三者在叶芽和花芽中祗是数量和比例方面有差别。初步明确，花芽叶中CTK/GA#-3比值明显高于叶芽叶，前者为4.02，后者为1.69。显然，CTK/GA#-3比值与苹果花芽分化有密切关系。文中对这二种激素的比值在成花过程中的作用进行了讨论。

VARIATION OF GIBBERELLINS, CYTOKININS AND ABSCISIC ACID IN VEGETATIVE AND FLOWER BUDS IN VARIOUS PERIODS OF APPLE TREE

In a study on the variation of gibberellins, cytokinins and abscisic acid in the leaves of vegetative and flower buds, 3 fractious of cytokinins were separated by Sephadex-LH 20 column. Fraction A consisted of 0-100 ml eluate, while fraction B 100-200 ml eluate, and fraction C 200-300 ml eluate. The three fractions of cytokinius in flower buds were remarkably higher than that in vegetative buds, especially the fraction C was much more than the fraction A and B, the contents of gibberellins were slightly higher in the flower buds than in the vegetative buds during the flower bud differentiation, but the ratio of cytokinins to gibberellius were higher than in the vegetative buds The former was 4.02, and the latter, was 1.69. A direct relationship was found between the ratio of endogenous cytokinins to gibberellins and the ability of the spur to produce flower buds. The role of the ratio of the two hormones in flower formation is discussed.