以各助剂临界胶束浓度(CMC)为参考,在室内条件下研究了添加不同浓度6种喷雾助剂对硝磺草酮防除禾本科杂草稗草及阔叶杂草反枝苋效果的影响,并探讨了各助剂的CMC值与硝磺草酮药效之间的关系。从助剂改变药液在植物叶片上的接触角与最大稳定持流量两个方面,分析了6种助剂对提高硝磺草酮除草效果的原因。结果表明:6种供试助剂添加浓度在不小于其CM C值时即可明显提高硝磺草酮在杂草上的有效沉积量,且均可不同程度地提高硝磺草酮对稗草及反枝苋的除草活性,对稗草的鲜重抑制活性比对反枝苋的高;其中GY-Tmax和S903效果较好,其次是GY-T12和QS-304,OP-10与S625效果略差。6种助剂通过降低药液在两种杂草叶片上的接触角、增大药液对靶标植物的最大稳定持流量,可提高硝磺草酮的除草效果。
The enhancement effects of six spray adjuvants with different concentrations on mesotrione in controlling Echinochloa crus-galli and Amaranthus retroflexus were investigated under greenhouse conditions, and meanwhile the relationship between critical micelle concentration (CMC) of adjuvants and the herbicidal effect of mesotrione were explored. On the other hand, the mechanism of the enhancement effects of spray adjuvants on mesotrione were analyzed from the point of the contact angle and maximum retention of pesticide solutions on the plant leaves. Results showed that all the six adjuvants with the concentrations above CMC could differently enhance the herbicidal effect of mesotrione by decreasing the contact angle and increasing the maximum retention, and had a better effect on controlling E. crus-galli. GY-Tmax and S903 had the best effect, while GY-T12 and QS-304 was better, the OP-10 and $625 had a general performance.