Exogenous metabolites spray, which identified from metabolomics analysis and transcriptomic analysis, can improve salt tolerance of Chinese cabbages (Brassica rapa L.ssp pekinensis)

Soil salinization is one of the causes of the decline of the available cultivated land. By improving the salt tolerance of vegetables, the abandoned salinized land can be effectively utilized, saving the arable land for major crops. We investigated the salt tolerance of hundreds of Chinese cabbage cultivars, by which the two most tolerant and sensitive cultivars were selected and studied by metabolome and transcriptome analyses. The results showed that, under salt stress, metabolites’ response was not closely correlated with gene expressions in the tested Chinese cabbages. However, some KEGG pathways were significantly regulated at both metabolic and transcriptional levels. Furthermore, we identified several critical metabolites in the co-regulated pathways, including acetyl-CoA, pyruvic acid, ATP, nicotinic acid and Coenzyme Q10, which could alleviate the salt stress level in the tested Chinese cabbage. Thus, our findings provide candidate agents which can be used to improve salt tolerance in Chinese cabbage.