%0 Journal Article
%T 炔草酯微乳剂药液在菵草叶片上的润湿和持留特性分析<br>Analysis of the wettability and retention of clodinafop-propargyl ME solutions on American sloughgrass Beckmannia syzigachne leaves
%A 许小龙
%A 徐广春
%A 徐德进
%A 顾中言
%A Xu Xiaolong
%A Xu Guangchun
%A Xu Dejin
%A Gu Zhongyan
%J 植物保护学报
%D 2015
%R 10.13802/j.cnki.zwbhxb.2015.03.025
%X 为科学使用除草剂防治菵草,采用Zisman图法测定了菵草叶片的临界表面张力及不同浓度炔草酯微乳剂药液的表面张力,利用表面张力法测定了炔草酯微乳剂中表面活性剂的临界胶束浓度及在菵草叶片上的接触角和最大稳定持留量.结果表明,菵草叶片的临界表面张力为31.3 mN/m.炔草酯浓度为676.1 mg/L时,药液表面张力为28.0 mN/m,此时药液中表面活性剂浓度即为临界胶束浓度;浓度为1 000.0、2 000.0 mg/L时,表面活性剂浓度大于临界胶束浓度,其表面张力分别为 27.7、27.8 mN/m,接触角均小于60°,润湿性好,最大稳定持留量分别为3.65±0.09、3.83±0.02 mg/cm2,均显著高于其余浓度;其余浓度下表面活性剂浓度均小于临界胶束浓度,药液表面张力大于菵草叶片的临界表面张力(500.0 mg/L除外),接触角介于75.9~125.9°之间,润湿性中等或差,最大稳定持留量相对较低,但均显著高于对照的0.47±0.10 mg/cm2.表明只有药液表面张力小于菵草叶片的临界表面张力,且药液中表面活性剂浓度达到临界胶束浓度时才能使药液在菵草叶片上具有较好的润湿性和较高的最大稳定持留量.<br>For scientific use of herbicides against American sloughgrass, Beckmannia syzigachne, the critical surface tension (CST) of American sloughgrass leaves was determined by using Zisman method. Surface tension of clodinafop-propargyl ME solutions at different concentrations was measured and the critical micelle concentration (CMC) of surfactant in clodinafop-propargyl ME was also measured according to the change of surface tension of the solution. Then the contact angle and maximum retention of the solution on American sloughgrass leaves were determined. The estimated CST value of American sloughgrass leaf surface was 31.3 mN/m. The CMC of surfactant in clodinafop-propargyl ME is 676.1 mg/L and surface tension value of the corresponding solution was 28.0 mN/m. The surfactant concentration of clodinafop-propargyl ME at the concentration of 1 000.0 or 2 000.0 mg/L was more than CMC and the surface tension of the solution was 27.7 and 27.8 mN/m, respectively. Their contact angles (＜60°) on American sloughgrass leaves were indicative of good wetting and maximum retentions were 3.65±0.09 and 3.83±0.02 mg/cm2, significantly higher than those of the solutions at other concentrations on American sloughgrass leaves. The surfactant concentrations of the other solutions (except 500.0 mg/L) were less than CMC and surface tension values were more than the CST of American sloughgrass leaves. Their contact angles in the range of 75.9-125.9° were regarded as moderate or poor wetting and maximum retentions were relatively low, but significantly higher than water on American sloughgrass leaves (0.47±0.10 mg/cm2). This study shows that only when the surface tension of herbicide solution is less than the CST of American sloughgrass leaves and the surfactant in pesticide solution reaches CMC, herbicide solutions have a good wetting ability and higher maximum retention on American sloughgrass leaves.
%K 炔草酯 菵草 表面张力 接触角&lt
%K br&gt
%K clodinafop-propargyl Beckmannia syzigachne surface tension contact angle
%U http://www.zwbhxb.cn/ch/reader/view_abstract.aspx?file_no=20150325&flag=1