苦木粗提物对氯氟吡氧乙酸致水稻药害的缓解效应及其生理机制OA

Fluroxypyr is an important herbicide for controlling broadleaf weeds in rice(Oryza sativa L.)fields.However,its improper application can cause phytotoxicity to rice,imposing substantial limitations on its use.To mitigate the phytotoxicity risk of fluroxypyr to rice,seed soaking with crude extracts and whole-plant bioassays were employed to investigate the alleviating effects of crude extracts from the Chinese medicinal herb Picrasma quassioides on fluroxypyr-induced phytotoxicity in rice and their influence on rice physiological and biochemical indices.The results showed that at a fluroxypyr concentration(calculated on the basis of active ingredient)of 210 g/hm2,seed soaking treatment with 2.5 g/L P.quassioides crude extract showed the best recovery effect on rice phytotoxicity.The relative recovery rate of plant height reached 161.56%at 14 d.P.quassioides crude extract seed soaking treatment significantly alleviated the adverse effects of fluroxypyr on rice chlorophyll content.It also reduced malondialdehyde(MDA)content while significantly increasing glutathione(GSH)content in rice seedlings and enhancing the activities of enzymes including glutathione S-transferase(GST),superoxide dismutase(SOD),peroxidase(POD),and catalase(CAT)in rice leaves.In summary,P.quassioides extract can effectively mitigate fluroxypyr-induced phytotoxicity in rice and exhibit potential for development as a botanical herbicide safener.