红和绿香椿芽贮藏过程中花青素和木质素含量及相关基因表达分析

Analysis of Anthocyanin and Lignin Contents and Expression ofRelated Genes in Red and Green Toona sinensis Buds during Storage

为了探究低温贮藏对香椿芽品质的影响,研究以贵州省织金县板桥镇红光村种植的红和绿香椿芽为材料,在4℃低温黑暗贮藏过程中对其叶片和叶柄进行外观形态和组织细胞学观察,花青素、木质素含量及其相关合成基因表达水平分析。结果表明,(1)红香椿芽贮藏3 d后色泽保持较好,而绿香椿芽贮藏1 d后开始出现黑色斑点,且黑色斑点的数量随贮藏时间的延长逐渐增加;(2)红香椿芽叶脉和叶柄木质部细胞比相应绿香椿芽小且数量少;红、绿香椿芽贮藏过程中次生细胞壁均逐渐增厚,且绿香椿芽叶脉和叶柄细胞染色程度较深;(3)在低温贮藏过程中,红、绿香椿芽花青素含量均降低,木质素含量均升高,红香椿芽花青素含量始终高于绿香椿芽,而其木质素含量始终低于绿香椿芽,且红香椿芽升降幅度较小;(4)在采后低温贮藏过程中,香椿芽叶片和叶柄中花青素和木质素相关合成基因的表达水平与花青素和木质素含量的变化趋势基本一致。研究表明,红、绿香椿芽贮藏过程中均发生了木质化和蒸腾失水,花青素含量降低,但绿香椿芽的变化更明显;香椿芽花青素和木质素含量的差异与其合成相关基因的表达水平具有相关性。

In order to explore the effect of low temperature storage on the quality of Toona sinensis buds,this study used red and green T.sinensis buds which from Hongguang Village,Banqiao Town,Zijin County,Guizhou Province as materials,observed the appearance morphological and histocytological,analyzed the anthocyanin and lignin content and their related synthetic genes expression levels in leaves and petioles of red and green T . sinensis buds during storage at 4 ℃ in the dark. The results showed that: (1)The color of red T . sinensis buds was better after 3 days of storage, while black spots began to appear ongreen T . sinensis buds after 1 day of storage, and the number of black spots gradually increased with theextension of storage time;(2) The leaf veins and petioles xylem cells of red T . sinensis buds were smallerand had fewer cells than that of the corresponding green T . sinensis buds;the secondary cell walls of bothred and green T . sinensis buds gradually thickened during storage, and the green T . sinensis buds veinsand petiole xylem cells stained more deeply;(3) The anthocyanin content decreased and the lignin contentincreased of both red and green T . sinensis buds during low temperature storage, and the anthocyanin contentof red T . sinensis buds was always higher than that of green T . sinensis buds, while its lignin contentwas always lower than that of green T . sinensis buds, and the rise and fall of red T . sinensis budswas smaller;(4) The expression levels of anthocyanin and lignin synthesis related genes in the leaves andpetioles of T . sinensis buds were basically consistent with the trends of anthocyanin and lignin contentsduring postharvest low temperature storage. It was found that both red and green T . sinensis buds underwentlignification and transpiration water loss during storage, and the anthocyanin content decreased, butthe change was more obvious in the green T . sinensis buds;the differences in anthocyanin and lignin contentof T . sinensis buds were correlated with the expression levels of their synthesis genes.