Effect of Sulfosulfuron, Metsulfuron-methyl and Sunflower Allelochemicals on Enzymes and Antioxidants Activities in Hordeum spantaneum and Avena fatua

In order to evaluate the effect of sunflower aqueous extract, Sulfosulfuron and Sulfosulfuron Metsulfuron-methyl on seedling growth and Some physiological and biochemical traits of Avena fatua and Hordeum spantaneum, this study was conducted in the Agricultural Faculty of Islamic Azad University (Shooshtar Branch) in a completely randomized design with 3 replications. Treatments included concentrations of 25, 50, 75 and 100% sunflower aerial organs aqueous extracts, Sulfosulfuron (27.7 g.ha-1), Sulfosulfuron 75% + Metsulfuron-methyl 5% (40 g.ha-1) and the control (nontreated plants). Results indicated that the weed dry weight, weed height, peroxidase, catalase and glutathione reductase activities, malondialdehyde concentration, sucrose synthase activity and photosynthesis rate of Avena fatua and Hordeum spantaneum influenced by experimental treatments. The lowest sucrose synthase activity (2.7 nmol/mg pro/ min) was observed in 100% sunflower extract. Sulfosulfuron and 100% sunflower extract had the lowest sucrose synthase in Avena fatua (2.6 and 2.4 nmol/mg pro/ min, respectively). In general, 75 and 100% sunflower extracts, and also the use of herbicides, caused cell membrane degradation, photosynthesis alleviation, and Avena fatua and Hordeum spantaneum seedlings growth reduction.