秋茶光合作用与品质成分变化的分析

Analysis of the Photosynthesis and Quality Components Changes in Autumn Tea

以茶树品种龙井43为材料,测定8月19日和9月23日不同时间点茶树冠层处光强、叶片温度、光合参数、品质成分含量及品质成分合成基因表达,初步明确光强、叶片温度对秋茶光合作用及三者对秋茶品质成分积累和相关合成基因转录水平的影响。结果表明,秋茶叶片温度以及叶肉细胞光合活性是影响净光合速率的关键原因,并且叶片温度可能通过调控儿茶素合成基因Cs PAL、Cs F3′5′H、Cs ANS、Cs UFGT及氨基酸合成基因Cs GS、Cs GOGAT、Cs TS1表达来影响秋茶茶多酚、氨基酸含量。另外,秋茶冠层处光强和净光合速率与部分品质相关合成基因的表达水平具有显著相关性。

The time courses of different indexes, including luminous intensity in the canopy, leaf temperature, photosynthetic parameters, quality component contents and the expressi on of genes related to quality component biosynthesis on August 19 th and September 23 th were measured in Longjing 43（Camellia sinensis cv. Longjing 43）. Using the results above, the effects of luminous intensity and leaf temperature on the tea photosynthesis and the influence of luminous intensity, leaf temperature and net photosynthesis rate on the accumulation of quality components and the transcription levels of biosynthetic genes could be confirmed preliminary. The results suggested that leaf temperature and photosynthetic activity of mesophyll cells were important physiological factors to affect the net photosynthesis rate of autumn tea. Moreover, the leaf temperature might influence the biosynthesis and accumulation of catechins and amino acids in autumn tea by regulating the expression of catechins biosynthe tic genes, such as Cs PAL, Cs F3′5′H, Cs ANS, Cs UFGT and amino acid biosynthetic genes, including Cs GS, Cs GOGAT and Cs TS1. Otherwise, the luminous intensity and the net photosynthesis rate of autumn tea were significantly correlated with the expression levels of genes related to catechin, amino acid and caffeine biosynthesis.