干旱胁迫对麦田茎叶型除草剂药效的影响

对麦喜、麦思达、巨星、快灭灵和好事达等5种茎叶型除草剂在麦田土壤干旱胁迫下的杀草速度和除草效果进行了研究。结果表明:5种除草剂的杀草速度及除草效果均在一定程度上受到土壤墒情的影响。用药前后土壤干旱可以使一些除草剂杀草速度变慢,除草效果明显降低。但不同除草剂受土壤干旱胁迫的影响程度不一样,其中麦思达和巨星受土壤干旱胁迫的影响较小,在用药前土壤相对含水量8.35％～9.03％时,用药后1周内浇水,仍可起到理想除草效果,药剂对杂草的鲜重防效达到92.6％～96.7％。而另外3种除草剂的药效受土壤干旱胁迫影响较大。

Study on the Influence of Water Stress on Weed Control Efficacy of Post-emergence Herbicides in Wheat Field

The influence of water stress on weed control efficacy of 5 post-emergence herbicides were studied in 2001. Soil water content affects both the speed of plant injuries and weed control efficacy of 5 herbicides. Weed control efficacy was lower and weeds were less sensitive in soil water stress treatment than in irrigated treatment before spraying. Mug-stang and Express were less affected by water stress among the herbicides. In the treatment when soil water content was less than 9. 03% during spraying time, weed control efficacy could reach 92. 6-96. 7% if spaying with Mugstang and Express.