Pathogenicity of Different Isolates of Entomopathogenic Fungi on Cotton Mealybug, Phenaccocus solenopsis Tinsley

Abstract

Cotton mealybug, Phenacoccus solenopsis Tinsley is a destructive pest of cotton, ornamental plants and many other crops due to its polyphagous nature. A study was conducted to check the efficacy of different local isolates of entomopathogenic fungi on 2nd nymphal instar of P. solenopsis under laboratory conditions by immersion method. Three entomopathogenic fungi; Beauveria bassiana (isolates Bb-01, Bb-08), Metarhizium anisopliae (isolates Ma-11.1, Ma-2.1) and Isaria fumosorosea (isolates If-2.3, If-02) showed percent mortalities of (61.0%, 85.0%), (78.0%, 56.0%) and (52.0%, 54.0%) with LC50 values of (4.25×108, 2.54×108 spores/ml), (3.26×108, 5.08×108 spores/ml) and (6.22×108, 7.20×108 spores/ml) with LT50 (6.43, 4.80), (5.43, 6.74) and (6.66, 6.69) days at highest con centrations. Amongst all isolates, B. bassiana isolate Bb-08 was highly efficient against cotton mealybug with highest percent mortality and lowest LC50 and LT50 values. The study showed that Bb-08 can be used in the IPM of P. solenopsis.