14种杀虫剂对西兰花小菜蛾的室内毒力测定及田间防效

Toxicity Measurement and Field Control Effects of Fourteen Pesticides on Plutella xylostella

为了筛选杀虫剂有效控制银川地区小菜蛾的为害,本文采用浸渍法测定了14种杀虫剂的室内毒力,并筛选出其中5种开展了田间药效试验。结果表明,5%甲维盐EC对小菜蛾的毒力最高,20%虫酰肼SC的毒力最低,48 h LC50分别为1.53 mg/L和1693.72 mg/L,14种供试杀虫剂的毒力大小依次为甲维盐>虫螨腈>阿维菌素>溴氰虫酰胺>苏云金杆菌>四氯虫酰胺>三氟甲吡醚>高效氯氟氰菊酯>氯虫苯甲酰胺>唑虫酰胺>茚虫威>乙基多杀菌素>氟啶脲>虫酰肼。田间防效试验结果表明,5种杀虫剂均在施药后3 d达到最高防效,其中10.5%三氟甲吡醚EC为大田试验中持效期最长、综合防效最好的杀虫剂,在保障对小菜蛾田间防效和减少农药使用量的前提下,建议在当地西兰花小菜蛾的防治中推广应用,推荐商品用量为900 mL/hm^(2)。

In order to effectively control Plutella xylostella in Yinchuan area,the indoor toxicities of 14 insecticides were determined by impregnation method,and 5 of them were screened out for field efficacy evaluation.The results showed that emamectin benzoate 5%EC had the highest toxicity to P.xylostella,and tebufenozide 20%SC had the lowest toxicity.Their LC50 values were 1.53 mg/L and 1693.72 mg/L at 48 h,respectively.The 14 pesticides with their toxicities from high to low,in order,were emamectin benzoate,chlorfenapyr,abamectin,cyantraniliprole,Bacillus thuringiensis,tetrachlorantraniliprol,pyridalyl,gammacyhalothrin,chlorantraniliprole,tolfenpyrad,indoxacarb,spinetoram,chlorfluazuron,and tebufenozide.The results of field control effect test showed that,among them,5 pesticides reached the highest control effect 3 days after application,and pyridalyl 10.5%EC had the longest duration and the best comprehensive control effect in the field test.When the field control effects of pesticides and their dosages are synthetically considered,it is recommended that pyridalyl 10.5%EC would be widely used,with a recommended dose of 900 mL/hm^(2),to control diamondback moth in local broccoli fields.