The Diphenyl-Ether Herbicide Oxyfluorfen: A Potent Inducer of Lipid Peroxidation in Higher Plants

Herbicide, Diphenyl Ether, Peroxidation, Antioxidants Measurements of ethane and ethylene as indices o f in vivo lipid peroxidation and o f chemicallyinduced stress, respectively, were done on mustard seedlings (Sinapis alba), treated with oxyfluorfen[2-chloro-l-(3-ethoxy-4-nitrophenoxy)-4-(trifluoromethyl)benzene]. When seedlings were exposed to low light intensity o f 14 W /m 2, only stress-ethylene production but not per­ oxidative ethane evolution was significantly higher over 1 0 days in herbicide-treated seedlings than in the untreated control. Exposure to high light intensity o f 390 W /m 2 did not increase stress-ethylene production in oxyfluorfen-treated plants after 24 h. Lipid peroxidation, however, measured as ethane evolution, was substantially higher after 24 h in herbicide-treated plants, exposed to high light intensity, than in the control, and peroxidation was directly related to strong oxidation o f antioxidants and to severe membrane damage.