砜吡草唑与二甲戊灵混配对棉田阔叶杂草的防效及安全性评价

Control effect of pyroxasulfone mixed with pendimethalin on broadleaf weeds in cotton filed and its safety evaluation

【目的】研究砜吡草唑与二甲戊灵混配对棉田阔叶杂草的防除效果,并评价其安全性。【方法】设置40%砜吡草唑SC和330 g/L二甲戊灵EC混配田间药效试验,评价各处理对棉田龙葵、灰绿藜、反枝苋、马齿苋和苘麻等阔叶杂草的防效及其对棉花生产的安全性。【结果】各处理棉花出苗率为80.56%~83.61%,与对照相比差异未达显著水平。砜吡草唑SC 120、180和240 g a.i./hm^(2)分别与330 g/L二甲戊灵EC 742.5 g a.i./hm^(2)混配后,药后30 d对棉田阔叶杂草的株防效分别为89.15%、92.03%和97.83%,药后45 d株防效分别为87.94%、91.49%和95.56%,鲜重防效分别为90.80%、93.16%和95.65%,混配药剂对棉田阔叶杂草的株防效和鲜重防效均优于单剂处理。各供试处理与对照相比,棉花增产幅度达9.89%~16.45%。【结论】40%砜吡草唑SC 120~180 g a.i./hm^(2)与330 g/L二甲戊灵EC混配可用作棉花田防除阔叶杂草,对棉花出苗安全。

【Objective】To confirm the control effect on the mixture of Pyroxasulfone and Pendimethalin to broadleaf weeds in cotton field.【Methods】Field trials were set up with mixture of 40%Pyroxasulfone SC and 330 g/L Pendimethalin EC to evaluate its safety to cotton and control effect on broadleaf weeds,such as Solanum nigrum,Chenopodium glaucum,Amaranthus retroflexus,Portulaca oleracea,Abutilon theophrasti.【Results】The results showed that germination rate of cotton was 80.56%-83.61%in treatment of mixed herbicides,there were no significant differences between treatment and contrast.The dosage of 330 g a.i./L Pendimethalin EC 742.5 g a.i./hm^(2)were mixed with Pyroxasulfone SC 120,180 and 240 g a.i./hm^(2)respectively,and their control effects of plant to broadleaf weeds were 89.15%,92.03%and 97.83%after 30 days and 87.94%,91.49%and 95.56%after 45 days,the control effects of fresh weigh to broadleaf weeds were 90.80%,93.16%and 95.65%respectively,the compound-dose treatments were more efficient than single-dose treatments on control effects of plant and fresh weight to broadleaf weeds.The yield of each treatment increased 9.89%-16.45%compared with control.【Conclusion】40%Pyroxasulfone SC 120-180g a.i./hm^(2)mixed with 330 g/L Pendimethalin EC are effective to control broadleaf weeds in cotton filed and safe to cotton.