Evaluation of efficacy of Triflusulfuron methyl on control of broadleaved weed in sugar beet fields

This study was conducted during 1997 and 1998 at agricultural research centers of Mashad, Dezful, Moghan and Karadj to reduce herbicide usage and protecting environment through application of Triflusulfuron with broad spectrum of weed control low residual and low application rates at the early growth stages of weeds and sugarbeet crop. The experimental design was a randomized complete blocks with 11 treatments in four replications. Herbicide treatments included post emergence applications of Triflusulfuron at 15 and 20 g a.i./ha at the cotyledonous stage of sugarbeet crop. Sequential applications of Triflusulfuron at 10 and 15 g a.i./ha at the cotyledonous stage of sugarbeet crops, Triflusulfuron + Phenmedipham at 15 g a.i./ha + 0.3kg a.i./ha, Choridazon+Phenmedipham at (1.6 + 0.3) kg a.i./ha, Phenmedipham at 0.3 kg a.i./ha at the cotyledonous stage of sugarbeet. Phenmedipham at 0.78 kg a.i./ha and Chloridazon at 4 kg a.i./ha at four leaf stage of sugarbeet crop, weed free and weedy controls. Effect of herbicide treatments on weed control and sugarbeet root yield were significantly different. Application of the mixture of Triflusulfuron + Phenmedipham at (15g+0.3kg) ai/ha had the highest level of weed control as compared to the weedy check and controlled broadleaved weeds by 78%. Weed free control and application of Triflusulfuron + Phenmedipham treatments with 45.13 and 36.94 t/ha produced the highest yield of sugarbeet root, respectively. However, weedy control with 10.53 t/ha had the lowest sugarbeet root yield.