玉米穗位叶碳氮代谢的关键指标测定

Determination of C-N Metabolism Indices in Ear-leaf of Maize (Zea mays L.)

碳、氮代谢是植物体内最主要的两大代谢过程,玉米一生中碳、氮代谢的协调在很大程度上决定着产量结果。用可见分光光度法对不同施氮水平下玉米穗位叶的碳氮代谢指标进行了检测。结果表明,施氮量在120～180kg/hm2间明显促进玉米穗位叶蔗糖的积累,在120～240kg/hm2间明显促进碳代谢的关键酶蔗糖磷酸合成酶(SPS)、氮代谢的关键酶硝酸还原酶(NR)和谷氨酰胺合成酶(GS)活性的增强。说明适宜的施氮量可明显促进玉米穗位叶碳氮代谢能力的增强,从而积累较多的同化产物满足籽粒灌浆的需求。

C and N metabolism are the main process in maize, and determine maize yield at a certain extent. C-N metabolism indices in ear-leaf of maize under different nitrogen supply rates （0, 120, 180, 240 kg/hm^2） were determined with Visible Spectrophotometry. The results showed that nitrogen supply obviously increased the content of sucrose in ear-leaf of maize under nitrogen supply rate of 120-180 kg/hm^2, and the activities of enzymes related to C-N metabolism such as nitrate reduetase （NR）, grutamine synthetase （GS）, and sucrose phosphate synthetase （SPS） in ear-leaf of maize under nitrogen supply rate of 120-240 kg/hm^2. Appropriate nitrogen supply can improve C and N metabolism in ear-leaf of maize which provide more accumulation to kernel.