Instituto de Microbiología y Zoología Agrícola, Instituto Nacional de Tecnología Agropecuaria, Las cabañas y Los Reseros s/n. CC 25, (1712) Castelar, Buenos Aires, Argentina.
J Invertebr Pathol. 2012 May;110(1):1-7. doi: 10.1016/j.jip.2012.01.010. Epub 2012 Feb 4.
The boll weevil (Anthonomus grandis) is the main pest of cotton in the Americas. The aim of this work was to evaluate isolates of the entomopathogenic fungi Beauveria bassiana sensu lato and Metarhizium anisopliae sensu lato virulent against A. grandis. Screening was performed to evaluate the pathogenicity of 28 isolates of M. anisopliae s.l. and 66 isolates of B. bassiana s.l. against boll weevil adults. To select the isolates, LC(50) values of the most virulent isolates were calculated, and compatibility between the fungi and insecticides was studied. In addition, the effects of these isolates on the feeding behavior of the adults were evaluated. Isolates Ma 50 and Ma 20 were the most virulent against A. grandis and their LC(50) values were 1.13×10(7) and 1.20×10(7) conidia/ml, respectively. In addition, these isolates were compatible with pyrethroid insecticides, but none with endosulfan. On the other hand, infected females reduced the damage caused by feeding on the cotton squares and their weight gain. This shows that entomopathogenic fungi cause mortality in the insects, but also these fungi could influence the feeding behavior of the females. In summary, these results indicate the possibility of the use of M. anisopliae s.l. as a microbiological control agent against boll weevils. Also, this species could be included in an Integrated Pest Management program.
棉铃象鼻虫（Anthonomus grandis）是美洲棉花的主要害虫。本工作的目的是评估对棉铃象鼻虫具有致病力的球孢白僵菌（Beauveria bassiana sensu lato）和金龟子绿僵菌（Metarhizium anisopliae sensu lato）的分离株。通过筛选来评估 28 株金龟子绿僵菌和 66 株球孢白僵菌对棉铃象鼻虫成虫的致病性。为了选择分离株，计算了最具致病力的分离株的 LC(50) 值，并研究了真菌与杀虫剂之间的兼容性。此外，还评估了这些分离株对成虫取食行为的影响。对 A. grandis 最具致病力的分离株是 Ma 50 和 Ma 20，其 LC(50) 值分别为 1.13×10(7)和 1.20×10(7)个孢子/ml。此外，这些分离株与拟除虫菊酯杀虫剂兼容，但与硫丹不相容。另一方面，受感染的雌虫减少了对棉铃的取食量造成的损害，并且它们的体重增加也减少了。这表明，昆虫病原真菌会导致昆虫死亡，但这些真菌也可能影响雌虫的取食行为。总之，这些结果表明，金龟子绿僵菌可以作为一种针对棉铃象鼻虫的微生物控制剂，也可以将该物种纳入综合虫害管理计划。
