外源GA3对枣树14C-光合产物向果实分配的影响

为探明外源GA3对刺树^14C－光合产物向果实分配的影响，应用^14C示踪技术，就GA3的作用机理进行了研究。结果表明：枣果实发育期施用外源GA3，施用GA3的方法不同，其效果亦不相同，赞皇大枣多年生二次枝喷50mg/L GA3后，标记叶片光合产物输出量较对照增加5.64%，花（果实）获得的^14C，光合产物量增加了4.48%；GA3涂抹冬枣果实，可提高果实的库活性，其中50mg/L GA3涂果效果明显好于20mg/L GA3涂果；50mg/L GA3涂抹冬枣果实同节位叶片，可阻止该叶片的^14C-光合产物外运，果实获得的光合产物减少。

Effect of exogenous GA3 on partitioning of photosynthates to fruit in Chinese date (Zizyphus jujuba Mill.)

The effects varied with the methods of GA 3 application during fruits development in Chinese Date. The photosynthates exported from labeled leaves increased by 5.64% when secondary branches over three- year-old were treated with 50 mg/L GA 3, 14C photosynthates imported to flowers and fruits increased by 4.48% than that of control; While fruits of Dongzao were treated with GA 3, sink activity of fruit enhanced, and the effect of 50 mg/L GA 3 application was better than 20 mg/L GA 3 application; When leaves were applied with 50 mg/L GA 3, the exportation of photo- synthates from labeled leaves decreased and the competitive activity of fruits to nourishment were reduced. The function mechanism of GA 3 was also discussed in the paper.