Studies on Camellia sinensis show that light and medium components had significant effects on metabolism of catechins in materials cultured in vitro and that DFR gene, LAR gene and PPO gene all have close relationship with it. For further study on molecular mechanism of metabolism of catechins and providing theoretical guidance for the deep development of catechins in C. nitidissima, calli rich in catechins were used as materials to study the variation of DFR gene expression, LAR gene expression, PPO gene expression and content of catechins and the correlation with each other in calli under different light source, hormones, carbon source or PHE treatments for 30 d. The results showed that all the above four detecting items reacted to in vitro treatments significantly. Under the above treatments, the ex-pression pattern of DFR gene and LAR gene was very similar. The correlation coefficients between the two under these treatments were between 0.710 and 0.889. The correlation of PPO gene expression and content of catechins was signifi-cantly negative under different carbon source treatments and their correlation coefficient was-0.696. DFR gene expres-sion was significantly positively related to the content of catechins under different PHE adding quantity treatments and the correlation coefficient was 0.786. LAR gene expression was also significantly positively related to the content of cat-echins under different PHE adding quantity treatments and the correlation coefficient was 0.564. MS solid medium sup-plented with 4 mg·L-16-BA, 0.6 mg·L-12,4-D, 30 g·L-1 sucrose and 0.6608 g·L-1 PHE was suitable for in vitro production of catechins. Content of catechins in calli cultured in this medium for 30 d was about 40.11 mg·g-1 DW. Based on the above research we concluded that similar to C. sinensis there was a close connection between DFR gene and LAR gene during metabolism of catechins in C. nitidissima and that the increase of expression of PPO gene caused the loss of catechins in C. nitidissima and that it was an effective way to add suitable amount of PHE for the increase of content of catechins in calli of C. nitidissima.%该研究以富含儿茶素的金花茶愈伤组织为材料,对不同光源、激素、碳源及苯丙氨酸处理30 d的愈伤组织中DFR表达量、LAR表达量、PPO表达量与总儿茶素含量的变化情况及四者两两之间的相关性进行了分析.结果表明:这4个检测项目均对以上处理有显著的响应;在以上各因素处理下,DFR与LAR的表达模式十分相似,其相关系数处在0.710~0.889之间;在不同碳源处理下,PPO表达量与总儿茶素含量的变化呈显著负相关关系,其相关系数为-0.696;在不同苯丙氨酸添加量处理下,DFR与LAR表达量变化均与总儿茶素含量变化呈显著正相关关系,其相关系数分别为0.786和0.564;适宜儿茶素离体生产的金花茶愈伤组织增殖配方为附加4 mg·L-16-BA、0.6 mg·L-12,4-D、30 g·L-1蔗糖与0.6608 g·L-1苯丙氨酸的MS固体培养基,其总儿茶素含量可达40.11 mg·g-1 DW.以上研究表明,与茶树相似,在金花茶中DFR与LAR在儿茶素代谢过程中密切相关;PPO表达量升高导致金花茶儿茶素损失;添加适宜浓度的苯丙氨酸作为前体物质是提高愈伤组织中总儿茶素含量的有效措施.
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