Type of joint effect and herbicidal activity in soybean field of the combination of flumetsulam, flumioxazin and acetochlor

To study the combined effect and herbicidal activity in soybean field of the combination of flumioxazin, flumetsulam and acetochlor, pot culture experiment and field efficacy tests were adopted to evaluate the type of the joint effect and the control efficacy on weeds in soybean fields of the mixtures respectively. The results of pot culture experiments showed that the type of joint effect was additive for the control of E. crusgalli, D. sanguinalis and A. theophrasti, and additive or synergistic for the control of A. retroflexus using the combination of flumetsulam, flumioxazin and acetochlor. And when the mass ratio was 2 : 3 : 45, the synergism of the mixtures was the highest for the control of A. retroflexus. The results of field experiments showed that the combination of flumetsulam, flumioxazin and acetochlor with the mass ratio of 2 : 3 : 45 had good efficacy against weeds in soybean fileds and was safe to soybean when the dosages of the active ingredients were 800 and 1 000 g/hm².