Biological Efficacy and Selectivity of Fluroxypyr and Florasulam in Control of Broadleaf Weeds in Winter Barley

Abstract

During 2021-2022 two fields trial with the winter barley variety "Lucian" was conducted. The studys was conducted in 2 different locations (Constanța and Călărași) and aimed to evaluate the biological activity of two herbicides based Fluroxypyr and Florasulam in control of broadleaf weeds in winter barley crops. The experiments were placed in randomized blocks, in 4 repetitions with a plot area of 100 m 2 . Efficacy and selectivity of the herbicides Flurostar Super SE (100 g/l fluroxypyr +1 g/l florasulam) and Tomigan XL 102.5 SE (100 g/l fluroxypyr + 2.5 g/l florasulam), applied at registered and higher rates, was evaluated. The herbicide application was done at the phenophase of the crop -1st -2nd stem node (ВВСН 30-32). The efficacy of the products by the 10 score scale of EWRS was recorded. The results were compared with untreated controls. The herbicide selectivity for the winter barley by the 9 score scale for phytotoxicity of EWRS was reported. The results obtained showed that the efficacy depends on the dose applied, the type of weeds and their density on square meter. The herbicide based floroxypyr and florasulam ensured a good efficacy in controlling of broadleaf weeds in winter barley, the best results being obtained at the higher dose. For both herbicides (Flurostar Super and Tomigan XL) at all evaluated rates signs of phytotoxicity for the crop were not observed.