Potential for entomopathogenic fungi to control Triatoma dimidiata (Hemiptera: Reduviidae), a vector of Chagas disease in Mexico

Abstract

The use of entomopathogenic fungi to control disease vectors has become relevant because traditional chemical control methods have caused damage to the environment led to the development of resistance among vectors. Thus, this study assessed the pathogenicity of entomopathogenic fungi in Triatoma dimidiata. Methods: Preparations of 108 conidia/ml of Gliocladium virens, Talaromyces fl avus, Beauveria bassiana Metarhizium anisopliae were applied topically on T. dimidiata nymphs adults. Controls were treated with the 0.0001% Tween 80 vehicle. Mortality was evaluated recorded daily for 30 days. The concentration required to kill 50% of T. dimidiata (LC50) was then calculated for the most pathogenic isolate. Results: Pathogenicity in adults was similar among B. bassiana, G. virens T. fl avus (p 0.05) differed from that in triatomine nymphs (p=0.009). The most entomopathogenic strains in adult triatomines were B. bassiana G. virens, which both caused 100% mortality. In nymphs, the most entomopathogenic strain was B. bassiana, followed by G. virens. The native strain with the highest pathogenicity was G. virens, for which the LC50 for T. dimidiata nymphs was 1.98 x108 conidia/ml at 13 days after inoculation. Conclusions: Beauveria bassiana G. virens showed entomopathogenic potential in T. dimidiata nymphs and adults. However, the native G. virens strain presents a higher probability of success in the fi eld, G. virens should thus be considered a potential candidate for the biological control of triatomine Chagas disease vectors.