二甲戊灵微囊悬浮剂防除旱直播稻田一年生杂草的效果

Control Effect of Pendimethalin Capsule Suspension on Annual Weeds in Dry Direct-seeding Rice Field

为了评价450 g/L二甲戊灵微囊悬浮剂对旱直播稻田一年生杂草的防效以及对水稻的安全性,开展了田间除草试验。结果表明:450 g/L二甲戊灵微囊悬浮剂在旱直播水稻播种后出苗前进行土壤封闭处理,对稗草的防效最好,药后45 d各剂量处理的株防效达到89.21%~97.93%,鲜重防效为88.89%~97.58%,其次是对千金子和异型莎草的防效,药后45 d各剂量处理的株防效分别为86.36%~97.65%和87.16%~97.44%,鲜重防效为86.29%~96.81%和87.54%~96.73%;药后45 d各剂量处理对矮慈姑的株防效和鲜重防效也分别为79.70%~94.85%和80.12%~95.75%;并且试验期间各药剂处理均未对水稻产生药害,但用量为260 mL/667m^(2)的处理水稻产量显著低于人工除草对照。因此,450 g/L二甲戊灵微囊悬浮剂在水稻旱直播田应用时宜在稻谷播种后出苗前兑水喷雾土壤,适宜用量为110~150 mL/667m^(2)。

The efficacy of 450 g/L pendimethalin capsule suspension(CS)on annual weeds and its safety to rice were evaluated in dry direct-seeding rice field.The experimental results showed that 450 g/L pendimethalin CS as soil treatment herbicide had the best effect on Echinochloa crusgalli at pre-emergence with the plant control efficacy reaching 89.21%-97.93%and the fresh weight control efficacy reaching 88.89%-97.58%on 45 d after treatment at the dosage of 1650 mL/hm^(2)-2250 mL/hm^(2);then to Leptochloa chinensis and Cyperus difformis,the plant control efficacy was 86.36%-97.65%and 87.16%-97.44%,respectively,and the fresh weight control efficacy was 86.29%-96.81%and 87.54%-96.73%,respectively;to Sagittaria pygmaea,the plant control efficacy was 79.70%-94.85%and the fresh weight control efficacy was 80.12%-95.75%.It was safe to rice,but at the dosage of 3900 mL/hm^(2),the rice yield was significantly lower than the control with artificial weeding.Therefore,450 g/L pendimethalin CS is recommended being applied with water in soil treatment at pre-emergence in dry direct-seeding rice field at the dosage of 1650-2250 mL/hm^(2).