Integrated Metabolomic and Transcriptomic Analysis of Antimony (Sb) Stress Response in Common Bermudagrass (Cynodon dactylon [L.] Pers.)

Antimony (Sb) is a toxic metalloid and has become an increasingly prevalent contaminant in ecosystems. Previous studies have reported that Sb has severe toxic effects on plant growth. However, the molecular mechanisms of the response to Sb stress in plants still remain unclear. In the present study, common bermudagrass (Cynodon dactylon [L.] Pers.), ‘Yangjiang’ cultivar, was treated with 200 mg/mL of antimony potassium tartrate solution. Integrated metabolomic and transcriptomic analysis was conducted to investigate the mechanisms of the Sb stress response of bermudagrass. The results showed that, after Sb stress treatment, soluble protein content, malondialdehyde (MDA) content, and catalase (CAT) activity increased by 180.56%, 280%, and 112.61%, respectively, compared to the control. Meanwhile, transcriptomic and metabolomic analyses identified numerous differentially expressed genes (DEGs) and differentially accumulated metabolites (DAMs) that were involved in the Sb stress response of bermudagrass, and many pathways, such as the carbon metabolism, photosynthesis and alanine, aspartate, and glutamate metabolism pathways, were also identified to be related to the Sb stress response of the bermudagrass plant by KEGG and GO enrichment. Overall, the present study revealed that photosynthesis and amino acid metabolism pathways play important roles in the Sb stress response of bermudagrass.