【摘要】 测定了丝瓜种子萌芽及子叶不同生长阶段的谷氨酰胺合成酶(GS)的活性及其同工酶的变化.除了发育上的变化外,光和外源氮对GS活性及其同工酶影响也是显著的.无论外源氮(N)是否存在,GS活性在种子萌芽和子叶生长初期是逐渐升高的,于第6天达到最大,其后活性逐步降低.在光照下,外源氮对GS1诱导作用大于GS2;在无氮下,光对GS2的刺激大于GS1;在暗处,外源氮对GS1和GS2两者都有诱导作用.更多还原

【Abstract】 The changes of glutamine synthetase (GS) and its isozymes were determined during seed germination and cotyledon developmental of towel gourd. The activities of GS and its isozymes were influenced by light and external nitrogen besides the development effect. Whether external nitrogen exist or not, GS activity was increased gradually in the seed germination and initial stage of cotyledon development and was the highest in 6 d. After this, the activity was declined. Under light, the induced activity of GS1 was higher than that of GS2. In external nitrogen-free, the promoted GS2 activity was more than that of GS1. Under the dark, the activities of both GS1 and GS2 were increased by the external nitrogen.更多还原