Integrated physiological and transcriptome analysis reveals potential toxicity mechanism of haloxyfop-P-methyl to Chiromantes dehaani

Haloxyfop-P-methyl is widely used in controlling gramineous weeds, including the invasive plant Spartina alterniflora. However, the mechanism of its toxicity to crustaceans is unclear. In this study, we adopted transcriptome analysis combined with physiologic changes to investigate the response of estuarine crab (Chiromantes dehaani) to haloxyfop-P-methyl. The results showed that the median lethal concentration (LC₅₀) of C. dehaani to haloxyfop-P-methyl at 96 h was 12.886 mg/L. Antioxidant system analysis indicated that MDA, CAT, GR, T-GSH, and GSSG might be sensitive biomarkers that characterize the oxidative defense response of the crab. In total, 782 differentially expressed genes were identified, including 489 up-regulated and 293 down-regulated genes. Glutathione metabolism, detoxification response and energy metabolism were significantly enriched, revealing the potential toxic mechanism of haloxyfop-P-methyl to C. dehaani. These results provide a theoretical foundation for further research on haloxyfop-P-methyl toxicity to crustaceans.