七种药剂对两种花生叶螨的室内毒力和盆栽药效测定

Toxicity and Pot Experiment of Seven Acaricides to Two Leaf Mites on Peanut

为明确7种常用杀螨剂对花生上二斑叶螨和朱砂叶螨的毒力差异和防治效果,为不同优势种群的防治提供高效药剂,采用浸虫法测定了7种杀螨剂对两种叶螨雌成螨和卵的毒力。毒力测定结果表明,螺虫乙酯对二斑叶螨成螨的毒力最高LC_(50)为1.213mg/L;哒螨灵、联苯肼酯、阿维菌素的毒力次之。阿维菌素对朱砂叶螨成螨的毒力最高LC_(50)为0.044mg/L;螺虫乙酯、哒螨灵、虫螨腈、联苯肼酯的毒力也较高;螺螨酯对两种成螨的毒力均最低。螺虫乙酯对二斑叶螨和朱砂叶螨卵的毒力均最高,LC_(50)分别为0.037mg/L、0.005mg/L。阿维菌素对二斑叶螨和朱砂叶螨成螨的毒力倍数差异最大,达247.8倍;其次是螺虫乙酯、虫螨腈毒力倍数为24.8倍和16.1倍;螺螨酯和阿维菌素对两种叶螨卵的毒力差异较大,分别达12.1倍和11.8倍。在盆栽花生上,43%联苯肼酯悬浮剂、22.4%螺虫乙酯悬浮剂、110g/L乙螨唑悬浮剂4000倍处理,对二斑叶螨的防效好,药后21d达83.75%～97.75%,显著高于其他药剂;7种药剂的4000倍液处理均对朱砂叶螨有很好的防效,药后21d达97.63%～100%。综上所述,除螺螨酯以外,6种供试药剂对朱砂叶螨成螨和卵的毒力均明显大于二斑叶螨,其中阿维菌素对两种成螨毒力差异最大。43%联苯肼酯悬浮剂4000倍液可有效同时防治两种叶螨,并有较好的速效性和持效性;其他6种药剂目前都是防治朱砂叶螨的高效药剂。本研究为防治叶螨合理用药提供了依据,对指导花生田叶螨的科学防治具有重要意义。

To determine the toxicity and control efficacy of seven acaricides to Tetranychhus urticae and Tetranychhus cinnabarinus on peanut and further find effective agents to control the different dominant populations,we measured seven selected acaricides to adults and eggs of two leaf mites by insect immersion method.Bioassay results showed that spirotetramat had the highest toxicity to Tetranychus urticae adluts,with LC 50 of 1.213 mg/L;followed by pyridaben,bifenazate,avermectin.Avermectin showed the highest toxicity to Tetranychhus cinnabarinus adluts,with LC 50 of 0.044 mg/L;followed by spirotetramat,pyridaben,chlorfenapyr,bifenazate.Spirodiclofen showed the lowest toxicity to both Tetranychhus urticae and Tetranychhus cinnabarinus adult mites.Spirotetramat had the highest toxicity to eggs of both two leaf mites,with the LC 50 of 0.037 mg/L and 0.005 mg/L,respectively.The toxicity index(LC 50)of abamectin between the two species of adult mites were the most different,and the ratio reached to 247.8 times.The difference on toxicity between spirotetramat and chlorfenapyr to two species of leaf mites is huge,with LC 50 ratio of 24.8 times for spirotetramat to two different leaf mites and LC 50 ratio of 16.1 times for chlorfenapyr to two different leaf mites respectively.The toxicity of spirodiclofen and avermectin to the eggs of both leaf mites were quite different,with LC 50 ratio of 12.1 times for spirodiclofen and LC 50 ratio of 11.8 times for avermectin to two different leaf mites,respectively.In the pot trial,43%bifenazate SC,22.4%spirotetramat SC,110 g/L etoxazole SC diluting 4000 times showed higher control efficacy to Tetranychhus urticae with 83.75%~97.75%control effect after application 21 days.Seven acaricides's diluting 4000 times had good control efficacy to Tetranychhus cinnabarinus,with 97.63%~100%control effect after application 21 days.In all,the toxicity of all miticides to Tetranychhus cinnabarinus adults and eggs were significantly higher than to Tetranychhus urticae except spirodiclofen.Avermectin showed the most significantly different toxicity index(LC 50)to two leaf mites;43%bifenazate SC diluting 4000 time provided effectively control to two leaf mites,with quick-acting and long residual efficacy.The other six acaricides also had effective control to Tetranychhus cinnabarinus.This study provides a basis for the rational insecticides use and has great significance for guiding the spider mites control in peanut field.