Entomopathogenic fungi with biological control potential against poultry red mite (Dermanyssus gallinae, Arachnida: Dermanyssidae).

Abstract

The poultry red mite, Dermanyssus gallinae (Arachnida: Dermanyssidae) is a pest that causes significant economic loss in laying hens for which control methods are limited. In this study, the effects of 20 indigenous fungal strains on poultry red mites in chicken farms were investigated. All experiments were conducted under laboratory condition at 28 ± 1 °C and 80 ± 5% humidity. A screening test showed that Metharizium flavoviride strain As-2 and Beauveria bassiana strain Pa4 had the greatest measured effect on D. gallinae at 1 × 10conidia/ml 7 days after application. In a subsequent does-response experiment, these strains also caused 92.7% mortality at 1 × 10conidia/ml within the same period. The LCof these strains was 5.5 × 10(95% CI: 0.8-37.5) conidia/ml for As-2 and 3.2 × 10(95% CI: 0.4-26.0) conidia/ml for Pa4, and their LTwere 1.94 and 1.57 days, respectively. The commercial Metarhizium anisopliae bioinsecticide Bio-Storm 1.15% WP, used as a comparator, had LCand LT1 × 10(95% CI: 0.1-7.9) conidia/ml and 3.03 (95% CI: 2.4-3.8) days, respectively. It is suggested that mycoacaricides could be developed using the best two fungal strains found in this study (As-2 and Pa4), providing potential for biological control of poultry red mites.