摘要

The protective effects of herbicide safeners, including 3-dichloroacetyl-2,2-dimethyl-1,3-oxazolidine (R-28725), 3-dichloroacetyl-2,2-dimethyl-4-ethyl-1,3-oxazolidine (Racemate), and its two enantiomers (R)-3-dichloroacetyl-2,2-dimethyl-4-ethyl-1,3-oxazolidine (R-enantiomer) and (S)-3-dichloroacetyl-2,2-dimethyl-4-ethyl-1,3-oxazolidine (S-enantiomer), on reducing the phytotoxicity of chlorimuron-ethyl to maize were investigated. Soaking the seeds in safeners increased the endogenous glutathione (GSH) content and glutathione-S-transferase (GST) activity of maize. When induced by R-enantiomer, the GST activity in vivo and in vitro increased 180 and 192% compared with control, respectively. R-28725 and R-enantiomer also increased the acetolactate synthase (ALS) activity inhibited by chlorimuron-ethyl from 45 to 100 and 97% compared with the control, respectively. The kinetic parameter V-max of GST in the maize treated with R-28725 and R-enantiomer increased by 103 and 92%, respectively, compared with the control. Our results suggest that R-28725 and R-enantiomer could significantly improve the GSH content, GST activity, and ALS activity of maize. Overall, maize could be protected from the injury caused by chlorimuron-ethyl.