Effects of linuron and dimethenamid on antioxidant systems in weeds associated with soybean

Abstract

Changes in antioxidant systems in soybean and associated weeds (Ambrosia artemisiifolia L., Chenopodium album L., Convolvulus arvensis L and Sinapis arvensis L.) were studied in relation to treatment with herbicides linuron and dimethenamid in the field experiment. Differences in the total superoxide dismutase (SOD) and catalase (Cat) activities were observed in plants after application of herbicide formulation. Quantities of superoxide (O(2).-) and hydroxyl (center dot OH) radicals and malonyldialdehyde (MDA), reduced glutathione (GSH) and total polyphenols content were also determined. In addition to this, potential antioxidant activity of the plant ethanolic extracts were assessed based on the scavenging activity of stable DPPH free radicals. Results obtained suggest that plants investigated 1) expressed different antioxidant systems in response to herbicide treatment; 2) enzymatic and non-enzymatic protective mechanisms were complementary; 3) some weed species showed distinctive and combined activity of several biochemical parameters, such as Ambrosia artemisiifolia.