Selection of varieties in mixed use of herbicides

The mixed use of herbicides is one of the important measures in the comprehensive management of weeds. The mixed use of herbicides can expand the herbicide spectrum, improve the herbicidal effect, prolong the suitable period of application, reduce the damage, reduce the residual activity, and delay the occurrence and development of herbicide resistance. It is an important measure to improve the application level of herbicides. Whether the two herbicides can be mixed, it is best to do a compatibility test. In the experiment, water is used as the carrier, and the herbicides to be mixed are added sequentially, in the order of water agent, wettable powder, suspending agent and emulsion. Each agent should be fully stirred and left for 30 minutes. If the emulsification, dispersion and suspension performance are good, it can be mixed. The selection of mixed varieties of herbicides should consider the following factors:

When ① herbicides are mixed with two or more herbicides, the herbicides should have synergistic or additive effect with each other, and their physical and chemical properties must be compatible, and the phenomena of precipitation, stratification and condensation should not occur after mixed use.

When ② was mixed with two or more herbicides, the herbicides could not antagonize each other, and the damage to crops was not easy to increase after mixed use.

The herbicides mixed with ③ had better be different kinds of herbicides or have different action mechanisms in order to maximize the herbicidal effect and delay the occurrence and development of drug resistance.

The herbicides mixed with ④ should have different herbicide spectrum or different sensitivity to the growth stage of weeds.

The herbicide varieties mixed with ⑤ should consider the combination of quick-acting and slow-acting, long-lasting and short-lasting, easy to spread and difficult to spread in soil, and herbicides with different action sites.

The variety selection and dosage of herbicides mixed with ⑥ should be determined comprehensively according to the field weed species, occurrence degree, soil texture, soil organic matter content, crop species, crop growth status and other factors.

The weeding effect of herbicides mixed with herbicides is affected by various factors. Before large-scale application, experiments, demonstrations or specific technical guidance should be carried out according to different proportions and different amounts of herbicides.