棉花不同品种叶片和纤维中蔗糖磷酸合成酶活性变化及其与糖含量的关系

利用山农棕02、丰抗6号、中棉45 3个品种在大田栽培的条件下，研究了叶片和纤维中蔗糖磷酸合成酶活性的变化及与糖含量的关系。结果表明，在3个品种的叶片和纤维中，蔗糖磷酸合成酶活性均出现双峰，在开花当天最高，花后18d次之，整体呈下降趋势；与此同时可溶性总糖和蔗糖的含量变化以及光合速率的变化也成相似的变化。3个品种中，丰抗6号蔗糖磷酸合成酶活性和含糖量最高，中棉45次之，山农棕02最低。3个品种的相应观测指标之间均呈极显著差异。

Dynamic Activity Changes of Sucrose Phosphate Synthase and Correlation with Sugar Content in Leaves and Fibres of Different Cotton Cultivars

The study showed that under field condition, the activities of Sucrose Phosphate Synthase(SPS) appeared double peaks at blooming day and 18 days post anthesis(DAP) in leaves and cotton fibres of Shannong Brown 02, Fengkang 6 and Zhongmiansuo 45; the first peak surpassed the second peak and it decreased as a whole. And simultaneously soluble sugar content, sucrose content and photosynthesis rate had the same changes. The values of SPS activity, soluble sugar content, sucrose content and photosynthesis rate were the highest in Fengkang 6, second in Zhongmiansuo 45, third in Shannong Brown 02. The three cotton cultivars differ very significantly (P<1%) in corresponding observation index.