药液表面张力和黏度对草甘膦药效的影响及其机理研究

Influences of surface tension and liquid viscosity on the efficacy of glyphosate and its mechanism

通过添加有机硅助剂和丙三醇调节草甘膦药液的表面张力和黏度,测定其对草甘膦药液液滴的物理性状及生物活性的影响。结果表明:降低药液的表面张力,雾滴的铺展直径增加,干燥时间缩短,药液的黏度以及在杂草叶片表面的最大稳定持留量没有显著性变化;草甘膦对杂草的防效表现为先升高后降低,对阔叶杂草最高目测防效和鲜重防效可提高42%和41%,对禾本科杂草防效可提高37%和37%。增加草甘膦的药液黏度,药液在杂草叶片上的最大稳定持留量增加,表面张力降低,对雾滴的干燥时间和铺展直径影响很小;草甘膦对阔叶杂草最高目测防效和鲜重防效可提高42%和41%,对禾本科杂草的防效可提高42%和42%。适当降低草甘膦药液的表面张力或增加其黏度均可提高其对杂草的防除效果。

This study was aimed to regulate the surface tension and viscosity of glyphosate by the organosilicone and glycerol, and measure the influence of physical characters of liquid droplets and biological activity. The results showed that, by reducing the surface tension of liquid, spreading diameter of the droplet was increased, and the drying time was shortened, but the viscosity of liquid and maximum retention on weed blade surface were not significantly changed. The inhibition rate to weeds firstly increased and then decreased, and the maximum control of visual and fresh weight of broadleaf weeds were increased by 37% and 37%, and those of grass weeds were increased by 42% and 41%. By increasing the viscosity, the maximum retention on weed blade surface was increased, and the surface tension was reduced, but the drying time of droplets and the spreading diameter were not significantly changed. The maximum control of visual and fresh weight of broadleaf weeds were increased by 42% and 41%, and those of grass weeds were increased by 42% and 42%. Moderate reduction of surface tension or increase of the viscosity of glyphosate could increase inhibition rate of weeds.