对西花蓟马高效金龟子绿僵菌菌株筛选及在花生田间的应用效果

Screening of Efficient Metarhizium anisopliae Strains for Frankliniella occidentalis and Its Application in Peanut Field

西花蓟马Frankliniella occidentalis是一种世界性检疫害虫,对包括花生在内的农作物造成极大威胁,金龟子绿僵菌在西花蓟马生物防治中可发挥重要作用。本文从23株金龟子绿僵菌中筛选出菌株M18-8-4,经紫外诱变得到F1、F2代菌株,测定了其及两代诱变菌株对西花蓟马的室内毒力,并对筛选到的高毒力菌株进行田间药效试验。室内毒力测定结果显示,在相同浓度孢子菌悬液下,诱变菌株F2-M18-8-4对西花蓟马的毒力最强,致死中时为2.13 d。以西花蓟马的校正虫口减退率、花生校正保叶效果和增产效果评价了金龟子绿僵菌F2-M18-8-4和3种化学农药(吡虫啉、噻虫嗪、乙基多杀菌素)对西花蓟马的田间防治效果。施药7 d、10 d后,金龟子绿僵菌F2-M18-8-4与3种化学农药对西花蓟马校正虫口减退率无差异;施药15 d后,金龟子绿僵菌F2-M18-8-4对西花蓟马的校正虫口减退率显著高于这3种化学农药,达79.52%,花生校正保叶效果最高,达63.58%,其次为乙基多杀菌素58.11%。在增产效果上,金龟子绿僵菌F2-M18-8-4防治西花蓟马对花生增产效果最好,达9.09%;其次为乙基多杀菌素7.40%。本研究结果表明筛选高毒力金龟子绿僵菌菌株,在适合的时机防治西花蓟马,可部分替代化学农药,并发挥良好的防治效果。

Frankliniella occidentalis is a worldwide quarantine pest,which can cause serious yield reduction of many leguminous host plants,including peanuts.Metarhizium anisopliae plays an important role in biological control of F.occidentalis.In this study,the M18-8-4 Strains were screened out from 23 M.anisopliae strains,of which the F1 and F2 strains were obtained by UV mutagenesis.In this study,the high toxic strains were obtained through toxicity tests in the laboratory,and their control of F.occidentalis was tested in the field.The results showed that,when tested at the same concentration of spore suspension,the strain F2-M18-8-4 had the strongest laboratory toxicity to F.occidentalis,with a median lethal time of 2.13 d.The control efficacies of F2-M18-8-4 and 3 chemical pesticides on F.occidentalis were evaluated in terms of the corrected population decline rate of F.occidentalis,the corrected peanut leaf protection rate,and the peanut yield increase rate.The corrected population decline rate of F.occidentalis did not differ significantly between F2-M18-8-4 and the 3 chemical pesticides at 7 days and 10 days post application,whereas at 15 days post application,the corrected population decline rate of F.occidentalis was higher in F2-M18-8-4 than in the 3 pesticides reaching 79.52%;and the peanut leaf protection rate was the highest,up to 63.58%,followed by Spinetoram at 58.11%.The peanut yield increase rate of F2-M18-8-4 was 9.09%.The results suggest the highly virulent strains can substitute for chemical pesticides in the control of F.occidentalis.