摘要： 为探讨化学封顶后棉株内源激素变化规律与果枝及结铃空间分布的关系。选用新陆早45号为试验材料，设置化学封顶（C）及2个对照组：不打顶（CK）和人工打顶（M），采用酶联免疫吸附法测定打顶后棉花倒四叶4种激素含量的昼夜变化。化学封顶后IAA含量较不打顶和人工打顶有明显的迅速下降趋势，并在168 h后仍保持较低水平；化学封顶后棉花GA₃含量与不打顶接近，这为棉花“二次生长”提供了一定的理论依据；化学封顶后棉花CTK上升速度较不打顶和人工打顶慢，但其峰值最大，并在168 h后仍维持较高水平；化学封顶后ABA含量一直维持较高水平直至试验结束；试验中各项指标峰值及底峰值均出现在化学封顶处理中。化学封顶能显著改变棉花倒四叶内源激素含量，同时化学封顶能有效控制棉株果枝长度，使结铃主要分布在中部和下部果枝，在顶部结铃上相较人工打顶有明显优势。

关键词: 棉花, 化学封顶, 倒四叶, 内源激素, 结铃空间分布

Abstract: The purpose of this study was to investigate the relationship between the changing of chemical detopping cottons' endogenous hormones and spatial distribution of boll branch. The present objective of this study was to measure four hormones,diurnal variation by Elisa inverse fourth leaf of cotton after detopping,North Xinjiang Early maturing cotton No.45 was the cotten variety,set the chemical(C)and two contrast group:no(CK)and artificial detopping(M). The results indicated that the IAA contention after chemical detopping(C)has decreased trend more obviously and rapidly than the no detopping(CK)and artificial detopping(M),and remained at a low level after 168 h;the GA₃ contention had no much difference about chemical topping(C)and no topping(CK),which provides a theoretical basis for the cotton "Secondary growth";the CTK contention of cotton after chemical(C)had slower rising speed than no topping(CK)and artificial topping(M),but it had maximum peak value,and remained at a higher level after 168 h;the ABA contention after chemical(CK)has maintained a high level until the end of the experiment. The experimental indexes'peak and bottom peak appeared in processing that proved chemical detopping could change the cotton endogenous hormone significantly inverse fourth leaf of cotton. Meanwhile chemical detopping could effectively control the cotton boll branch length,which were distributed mainly in the middle and lower branch,at the top of ball has obvious advantages compared to artificial detopping. The research provides certain theoretical basis for chemical detopped cottons'spatial distribution of boll and branch is regulated by the endogenous hormones.

Key words: Cotton, Chemical detopping, Inverse fourth leaf, Endogenous hormone, Spatial distribution of boll

中图分类号: 

• S562.01