Transcriptome and Metabolome Reveal Salt-Stress Responses of Leaf Tissues from Dendrobium officinale

Kimura et Migo is a precious traditional Chinese medicine. Despite . displaying a good salt-tolerance level, the yield and growth of . were impaired drastically by the increasing soil secondary salinization. The molecular mechanisms of plants' adaptation to salt stress are not well documented. Therefore, in the present study, plants were treated with 250 mM NaCl. Transcriptome analysis showed that salt stress significantly altered various metabolic pathways, including phenylalanine metabolism, flavonoid biosynthesis, and α-linolenic acid metabolism, and significantly upregulated the mRNA expression levels of , , , , and involved in the jasmonic acid (JA) biosynthesis pathway, as well as rutin synthesis genes involved in the flavonoid synthesis pathway. In addition, metabolomics analysis showed that salt stress induced the accumulation of some compounds in leaves, especially flavonoids, sugars, and alkaloids, which may play an important role in salt-stress responses of leaf tissues from . Moreover, salt stress could trigger JA biosynthesis, and JA may act as a signal molecule that promotes flavonoid biosynthesis in leaves. To sum up, plants adapted to salt stress by enhancing the biosynthesis of secondary metabolites.