Effect of different degrees of withering on gene expression and metabolite content of Wuyi rock tea leaves

Abstract

The degree of withering significantly affected the formation of tea quality. This study analyzed the effects of light withering (LW), moderate withering (MW) and heavy withering (HW) on tea quality jointly by transcriptome and metabolomics. It was found that LW was more beneficial in increasing gene expression of the ko00500, ko00511, ko00940, ko00944, ko00941, ko00740 and ko02010 pathways in tea leaves, thereby increasing the content of quinones, phenolic acids, lignans and coumarins, and flavonoids; MW was more beneficial in increasing gene expression of ko00500, ko00511, ko00130, ko00380 and ko00520 pathways, thereby increasing the content of terpenoids, organic acids and lipids. The aroma intensity was highest in moderately withering tea leaves and bitterness intensity was highest in lightly withering tea leaves, while the intensity of mellowness, fresh and brisk taste was significantly higher in MW and LW than in HW. This study provides an important basis for guiding the processing of Wuyi rock tea with different flavors.