3种介质盆栽辣椒根系黄酮类化合物及其合成酶基因影响研究

Effect on Metabolites and Their Synthetases of Flavonoids in Root Under 3 Media Potting Capsicum annuum

摘要:

为了解辣椒(Capsicum annuum)连作障碍中根系响应机制，以基质土、轮作土和连作土3种介质盆栽辣椒，待进入盛果期取其根系进行组学研究，分析辣椒根系黄酮类化合物具体成分及其合成酶基因信息。结果表明，3种介质盆栽辣椒根系中共检测到31种黄酮类化合物；相比基质土，这些黄酮类化合物在轮作土和连作土2种栽培条件下，含量显著提高的有天竺葵素、矢车菊素(2种)、飞燕草素、新橙皮苷和槲皮素共6种，仅锦葵素1种黄酮类化合物含量显著降低(分别下降82.37%和91.29%)。黄酮类化合物合成共涉及到202个酶基因，其中家族基因较多的主要有细胞色素P450 (15个)和尿苷二磷酸糖基转移酶(14个)等；相比基质土，这些黄酮类化合物主要合成酶基因在轮作土和连作土2种栽培条件下，差异表达量显著差异的共38个，具体包括类黄酮合成酶基因23个、花青素合成酶基因3个、异黄酮合成酶基因7个、黄酮和黄酮醇合成酶基因5个；其中尿苷二磷酸糖基转移酶基因在花青素合成代谢(1个)以及黄酮和黄酮醇合成代谢(3个)中，均在连作土栽培下表达量显著提高(分别提高了150.00%、161.45%、92.77%和773.50%)。因此，连作等逆境胁迫能显著提高辣椒根系中大多数黄酮类化合物含量，其合成酶基因上下调表达趋势规律不明显。

Abstract:

To understand the root response mechanism of Capsicum annuum under continuous cropping obstacles, three types of media, namely substrate soil (CSS), rotation soil (CRS) and continuous cropping soil (CCS), were used to pot the peppers. The root systems were collected when they entered the fruiting period for omics research to analyze the specific components of flavonoids and the information of their synthase genes in the root systems of peppers. The results showed that a total of 31 flavonoids were detected in the root systems of peppers in the three types of media. Compared with CSS, the contents of six flavonoids, namely pelargonidin 3-O-caffeoyl-β- d-glucoside, cyanidin 3-O-glucosides (2 types), delphinidin 3-O-β-d-glucoside, neohesperidin, quercetin 3-O-β-d- glucosyl-β-d-glucoside, were significantly increased in the two cultivation conditions of CRS and CCS, while only one flavonoid, malvidin-3-rutinoside-5-glucoside, was significantly decreased (by 82.37% and 91.29%, respectively). The synthesis of flavonoids involves 202 enzyme genes, among which the families with more genes mainly include cytochrome P450 (15) and UDP glycosyltransferase (14). Compared with CSS, the expression of main synthase genes of these flavonoids in CRS and CCS were significantly different, including 23 flavonoid synthase genes, 3 anthocyanin synthase genes, 7 isoflavone synthase genes, and 5 flavone and flavonol synthase genes. Among them, the expression of UDP glycosyltransferase genes in anthocyanin synthesis metabolism (1) and flavone and flavonol synthesis metabolism (3) were significantly increased on CCS cultivation (by 150.00%, 161.45%, 92.77% and 773.50%, respectively). Therefore, continuous cropping and other adverse stress could significantly increase the content of most flavonoids in the root systems of peppers, and the up and down regulation trends of their synthase genes were not obvious.