The effect of mixing herbicides of clodinafop-propargyl and sulfosulfuron in wheat, wild oat (Avena ludoviciana Dur.) little seed canary grass (Phalaris minor Retz.)

The accurate application of herbicides for selective and economic control of weeds without harming the environment and crops is one of the most important successes in modern agriculture. To investigate the additive, synergism and or antagonism effect of clodinafop-propargyl and sulfosulfuron tank mixture on wheat winter wild oat and little seed canary grass weeds using isobole curves, a series of experiments were conducted at the greenhouse of Gorgan University of Agricultural Sciences and Natural Resources based on completely randomized design with 3 replicates. Herbicides were applied at 8 rates of 0, 0.1, 0.2, 0.4, 0.6, 0.8, 1, 2 X of recommended dose and tank mixture ratios of (0:100), (25:75), (50:50, (25:75), (100:0). Log-logistic function for dry weight of plants was fitted against differential doses of herbicides for each mixture and the dose required to inhibit 50% growth (GR50) was estimated. Then, isobole curves were used to determine the effect of clodinafop-propargyl and sulfosulfuron mixtures. The results showed that the rates of clodinafop-propargyl and sulfosulfuron required for 50% reduction in winter wild oat and little seed canary grass growth were 0.437 and 1.719, and 0.312 and 0.952 recommended dose of this herbicides. GR50 increased as sulfosulfuron rates increased. The mixture of clodinafop-propargyl and sulfosulfuron at recommended dose had no effect on wheat.