Study On The Spatiotemporal Expression Of Theanine And Catechin Biosynthesis Genes In Huangjincha(Camellia Sinensis)

C.sinensis(L.)O.Kuntz,Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 has excellent quality and early germination,and its high content of amino acids gives tea soup a brisk taste.The study of the spatiotemporal expression of theanine and catechin biosynthesis genes in Huangjincha was of great significance for understanding the accumulation of theanine and catechins in Huangjincha.In this study,Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 were used as the main materials.High-performance liquid chromatography and real-time fluorescent quantitative PCR were used to analyze Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 picked at different times and leaf positions and Fudingdabaicha,Bixiangzao Zhuyeqi and Baihaozao.As a result,the contents of theanine and catechins and their biosynthetic genes expression of these samples were studied.The correlation between the content of theanine,catechins and the expression of biosynthetic genes was analyzed.The results were as follows:(1)Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 with one bud and two leaves picked on March 11,2020,March 18,March 28,and July 24 were the research objects.The experimental results showed that the theanine content was Mar.18>Mar.11>Mqr.28>Jul.24,and the EGC content and the non-ester catechin content were higher in the summer(Jul.24)than in the spring(Mar.11 、 Mar.18 、 Mar.24).Fluorescence quantitative PCR showed that the expression levels of CsGDH1,CsGDH2,CsGABA-T,and CsUGGT genes in summer was higher than those in spring,and CsF3’H gene expression in summer was lower than in spring.The correlation analysis results showed that the theanine content was significantly negatively correlated with the expression of CsTS1,CsLHT,CsGDH1,CsGDH2,and CsGABA-T(p<0.05);and the EGC content was significantly positively correlated with the expression of Cs4 CL,CsANR,and CsUGGT(p<0.05),significantly negatively correlated with F3’5’H gene expression(p<0.05);D,L-C content was significantly positively correlated with CsC4 H gene expression(p<0.05);EC content was significantly negatively correlated with CsF3’5’H gene expression(p<0.05),and significantly positively correlated with the CsUGGT gene expression(p<0.05).(2)One bud and two leaves,the third leaves,the fourth leaves,and tender stems of Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 picked on March 28,and one bud and two leaves,the third leaves,the fourth leaves,the fifth leaves,and tender stems of Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 picked on July 24,were the research objects.The experimental results showed that the content of theanine in the tender stems of Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 was the highest,while the content of EGCG,GCG and ECG was the lowest.The expression of CsADC gene in each part of Huangjincha 168 was lower than that of Baojing Huanjincha 1and Huangjincha 2.Correlation analysis results showed that the theanine content of different parts of the Baojing Huangjincha 1,Huangjincha 2,and Huangjincha 168 was significantly positively correlated with the relative expression of CsALT gene(p<0.05),and significantly negatively correlated with the expression of CsTS1,CsNR,CsGS2,and CsGDH1(p<0.05);EGC content was significantly positively correlated with Cs4 CL,CsANR gene expression;D,L-C content and CsC4 H gene expression,EGCG content Cs4 CL,CsANR,CsUGT84 A gene expression was significantly positively correlated.(p<0.05).(3)Baojing Huangjincha 1,Huangjincha 2,Huangjincha 168,Fuding Dabai cha,Bixiangzao,Zhuyeqi,Baihaozao with one bud and two leaves were the research objects.The experimental results showed that theanine content was: 1.100%-1.711%(March 28),0.319%-0.524%(July 24);The EGC content of Baojing Huangjincha No.1 was significantly higher than other varieties(p <0.01).The results of correlation analysis showed that the content of theanine was significantly negatively correlated with CsNR,CsGDH2,and CsGABA-T gene expression(p<0.05).EGC content was significantly positively correlated with Cs4 CL and CsLAR gene expression,and significantly negatively correlated with CsDFR gene expression.EC content was significantly positively correlated with CsLAR and CsUGGT gene expression(p<0.05).