棉花花芽分化及部分内源激素变化规律的研究

Studies on flower bud differentiation and changes of endogenous hormones of Gossypium hirsutum

棉花 ( Gossypium hirsutum)的腋芽原基 ,有的将来发育成叶枝 ;有的将来发育成果枝。这 2种不同命运的腋芽 ,在其刚分化的初期就表现出了不同的解剖学特征。将来发育为叶枝的腋芽 ,其生长锥呈圆锥形或扁圆球形 ,体积较小 ,原套层数为 1～ 2层 ;而将来发育为果枝的腋芽 ,其生长锥为圆柱形 ,顶端表面平坦 ,体积较大 ,原套层数为 2～ 3层。从子叶展平后到肉眼可见花芽 (现蕾 ) ,连续测茎尖的内源 ABA及 IAA的含量 ,发现在花原基形态分化始期 ,内源 ABA含量达最大值 ,而内源 IAA含量却达最低值。由此我们推测 ,内源 ABA含量升高或IAA含量降低 ,皆有利于棉花的花芽分化。

Some axillary buds of \%Gossypium hirsutum\% developed into vegetative shoots and some developed into reproductive shoots.There are different in the two kinds of axillary buds.The apical meristems of the vegetative shoot apexes were like half balls or tapers and small.There are 1~2 layers tunica cells in the vegetative shoot;while the apical meristems of the reproductive apexes were like column and big.There are 2~3 layers tunica cells in the reproductive shoot apexes whose surface were flat.The results of endogenous hormone experiment were that the contents of ABA appeared a peak and the contents of IAA appeared evident decrease when flower buds began to differentiate.It was concluded that increasing the content of ABA or decreasing the content of IAA could accelerate flower bud differentiation.