Penthiopyrad, a chiral pesticide, has been widely used in agricultural production. However, systematic evaluation of stereoselective bioactivity and biotoxicity of penthiopyrad in soil environment is insufficient. In this study, the stereoselective bioactivity of penthiopyrad against three soil-borne disease pathogens and its stereoselective biotoxicity to soil non-target organisms were investigated. The present results showed that the bioactivities of S-penthiopyrad were 546, 76 and 1.1-fold higher than those of R-penthiopyrad due to their different interaction modes with SDH in different target pathogens. S-penthiopyrad was more persistent in the soil environment and had stronger bioaccumulation than R-penthiopyrad. The accumulation of penthiopyrad in earthworms induced the response of detoxification system, resulting in the significant increases in the activity of detoxifying enzymes, such as GST, CarE, and CYP450. Additionally, both S-penthiopyrad and R-penthiopyrad induced cell apoptosis, intestinal damage and differentially expressed genes in earthworms, especially S-penthiopyrad. Furthermore, S-penthiopyrad has stronger binding capacity with COL6A and ACE proteins, while Rpenthiopyrad has stronger binding capacity with CYP450 family proteins, which may be the main reason for the differences in biotoxicity between PEN enantiomers. Considering the differences in bioactivity and biotoxicity of penthiopyrad enantiomers, as well as the modes of action of pesticides on target and non-target organisms, Spenthiopyrad has greater potential for future development.

Fosthiazate is a widely used organophosphorus nematicide that resides in the soil and controls soil root-knot nematodes. However, whether it has toxic effects on non-target soil organisms such as earthworms is unclear. Therefore, in this study, a 28-day experiment of fosthiazate exposure was conducted using the Eisenia fetida as the model organism. The results showed that fosthiazate stress caused excessive production of reactive oxygen species (ROS), increased the levels of malondialdehyde (MDA) and 8-hydroxy-2-deoxyguanosine (8-OHdG), and decreased the activities of superoxide dismutase (SOD) and catalase (CAT), suggesting that fosthiazate induced oxidative stress and DNA damage in E. fetida. Acetylcholinesterase (AChE) activity was significantly reduced, and the expression of its related functional genes was also altered, demonstrating that fosthiazate damaged the nervous system of E. fetida, which was further confirmed by AlphaFold2 modeling and molecular docking simulations. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis indicated that fosthiazate exposure may induce apoptosis, inflammation, and viral infection in E. fetida, which adversely affect the organism. This study provides reference data for the ecotoxicity of fosthiazate.