香荚兰花芽分化至萌发期内源激素的变化

以香荚兰 (Vanillafragrans)为材料 ,研究不同栽培条件下花芽分化和萌发期内源激素变化 ,分析和探讨内源激素在花芽分化和萌发中的作用 ,香荚兰花芽分化时期茎里的激素含量降低 ,芽里激素含量升高 ,其中相对高的ZR和ZR ABA有利于分化 ,IAA和IAA ABA的一定增加也利于分化 ,过高或没有IAA的增加则不利于花芽分化。大多数花芽形成于倒垂茎蔓上 ,花芽分化期 (11～ 12月 ) ,倒垂茎蔓的茎里生长类激素含量降低大于竖立茎蔓 ,芽的激素含量增高则多于竖立茎蔓 ,倒垂茎蔓的这种变化可能是有利于花芽分化。香荚兰生长中顶端优势明显 ,去顶后侧芽里ZR、GA、IAA增高 ,这与 11～ 12月去顶促进倒垂茎蔓开花可能有关。

The Change of Endogenous Phytohormones in Vanilla fragrans from Flower Bud Differentiation to Germination Phases

In this paper we studied the changes of endohormone of Vanilla fragrans cultivated at different cultivated conditions,analyzed and discussed the action of endohormone at the stages of flower bud differentiation and flowering. In flower bud differentiation period,there are decline of endohormone level in vine and rise of endohormone level in flower bud.Relatively high ZR content and ZR/ABA ratio benefited for its differentiation,and moderately increasing of IAA content and IAA/ABA ratio also did same,but too high IAA content or no increasing of the content was unfavorable for it. Most of flower buds forms in the cernuous vine.The content of growth helping hormone in cernuous vine decreased more than it in antrorse vine at the stage of flower bud differentiation from November to December,but it in buds was more than in the antrorse vine.This change in cernuous vine might prompt the flower bud differentiation. The apical dominance of Vanilla was outstanding during growing,ZR,GA,IAA contents in lateral buds has increased after the apex was removed.It might correlative with the prompting blossom of the antrorse vine from November to December.