In-vitro Evaluation of Entomopathogenic Fungus Metarhizium anisopliae against the Cattle Tick Rhipicephalus (B.) microplus (Acarina: Ixodidiae)

Abstract

The research was conducted to evaluate the pathogenicity of fungus Metarhizium anisopliae on the egg and adult stages of the cattle tick Rhipicephalus (B.) microplus. The fungal powder containing conidia procured in the year 2012 and manufactured in the year 2016 was used in the research to compare their efficacy against egg and adult stages of Rhipicephalus (B.) microplus ticks. The susceptibility of the tick to the species of entomopathogenic fungi was evaluated by treating engorged female ticks and eggs with fungi at concentrations 1g×10⁸ conidia/litre, 2×10⁸ conidia/litre 4g×10⁸ conidia/litre, 5g×10⁸ conidia/litre6g×10⁸ conidia/litre. The treatment of ticks and egg was followed as per standard procedure. The both fungal treatments showed at par results in terms of mortality of adult ticks, reduction in egg laying capacity and hatchability of the treated eggs in comparison with the control and found to be concentration dependent. The hatching rates by the treated groups were inversely proportional to the concentration of conidia used.  The results showed that the biological control of R. (B.) microplus by M. anisopliae infection might constitute an additional method to integrated tick management.