Susceptibility of two important cotton insects, Spodoptera littoralis and Agrotis ipsilon (Lepidoptera : Noctuidae)‎ to the entomopathogenic fungus Metarhizium anisopliae

الملخص EN

Laboratory bioassay of the fungus Metarhizium anisopliae included different stages of two important cotton insects, Spodoptera littoralis and Agrotis ipsilon, under different concentrations of fungus.

The fungus proved virulent against eggs and larvae of both insects.

Treatment eggs of both insects reduced rate of hatchability.

It was evident that eggs and larvae of both insects were susceptible to fungul infection, and most of hatched larvae from treated eggs failed to devleop to adults and dead.

LC50 of both eggs and larve of S.

littoralis was 1.7 x 103 and 2.5 x 103 spores/ml, respectively.

LC50 for A.ipsilon eggs was 2.5 x 103 spores/ml, wgile it was 5.5 x 103 spores/ml for larvae.

S.littoralis appeared more susceptible to fungal infection than A.ipsilon through out all the ages, and recorded more mortality in larvae, pupae, and adults during the development of the larvae emerged from the treated eggs.

The aim of this study is to investigate possibility of using M.anisopliae as a biological control agent against S.littoralis and A.ipsilon.