Bioactivity Evaluation of the Herbicide with 20% Nicosulfuron Plus Cyanazine

Greenhouse and field experiments were conducted to evaluate the joint effect and bioactivity of nico-sulfuron plus cyanazine mixtures.The results showed that nicosulfuron plus cyanazine was additive and synergistic in Amaranthus retroflexus L.and Digitaria sanguinalis(L.) Scop.controlled respectively,and it was compatible to mix nicosulfuron and cyanazine together in the ratio of 1-4:12.5.Preparation of the mixtures was nicosulfuron plus cyanazine 20% OF(oil miscible flowable concentrate).The mixtures should be applied at 3-5 leaf stage of maize and 2-5 leaf stage of weeds,and the reduction rates of amount and fresh weight of weeds were up to 83.6%-94.3% and 92.7%-99.2% at 180-300 g/ha after 30 days treatment.Within the recommended period and dosages,application of the mixtures was safe for maize and could result in yield increasing by 0.6%-6.4%,on the other side,the maize safe-ty and weeds control would decrease when the mixtures applied over 7 leaf stage of maize and 5 leaf stage of weeds.