脐橙果实发育过程中有机酸合成代谢酶活性的变化

 以红桔砧10 年生罗伯逊脐橙为试材, 研究了果实发育过程中有机酸代谢相关酶活性的变化及其与有机酸积累的关系。结果表明: 在整个果实发育过程中, 柠檬酸合成酶(CS) 和磷酸烯醇式丙酮酸羧化酶(PEPC) 活性与有机酸含量呈极显著正相关。这不仅证明脐橙果实中存在通过CO₂ 固定合成有机酸的途径, 还说明CS、PEPC 是有机酸合成的关键酶, 抑制CS 的活性能降低果实中有机酸的生成量。

Changes of Organic AcidSynthetase Activity during Fruit Development of Navel Or ange(Citrus sinesis Osbeck)

Using Robertson Navel( madarin rootstock ten years)as a testing material,the activity variance of enzyme related to organic acid metabolism and its relationship with the organic acid accumulation were studied.The result shows:There is a significantly positive correlation between the activity of Citrate synthase(CS)or Phos phoenolpyruvate carboxylase(PEPC)and organic acid,Their correlation coefficient(r)are equal to 0.9160 and 0.8779 respectively.This not only proves that CO 2 fixation is a main pathway of organic acid synthesis in Navel orange fruit;but also proves that CS and PEPC are the key enzymes of organic acid synthesis,and efficiently inhibiting CS and PEPC activity could reduce the organic acid content of orange fruit.