Toxicological Studies and Histopathological Changes on Black Bean Aphid, Aphis craccivora Induced by Entomopathogenic Fungi, Metarhizium anisopliae and Purpureocillium lilacinum

Document Type : Original Article

Authors

1 Botany and Microbiology department, Faculty of Science, Suez University

2 Plant Protection Research Institute Agriculture Research Center Dokki Giza Egypt*

3 Plant Protection Research Institute Agriculture Research Center Dokki Giza Egypt

Abstract

Toxicological, histopathological and ultrastructure studies of Metarhizium anisopliae and Purpureocillium lilacinum infected Aphis craccivora nymph were investigated in this study. comparison between fungal spore suspensions and fungal culture filterates virulence effects of the two tested entomopathogenic fungi  against A. craccivora  nymph were done under laboratory condition and the toxicological bioassay results revealed that P.lilacinum has a high toxic effect than M. anisopliae in which the  LC50 of fungal spore suspensions and culture filterates after 7 days post-treatment was (7×102, 1×105 spore/ml and 3.2, 4.7 % ) for P. lilacinum and M.anisopliae, respectively. Treated nymph with spore suspensions was examined using both light and transmission electron microscope to study histopathological and ultrastructure changes compared with the control one. This comparison suggested that there is a deformation of the nymph body, complete destruction of all internal organs with an extensive invasion of the fungal spores throughout all internal body regions.

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