Efficiency of Certain Entomopathogenic Bacteria, Fungi with Pesticides for Controlling Spodoptera littoralis

Abstract

This study was conducted to identify the susceptible stages of the cotton leafworm, Spodoptera littoralis to the entomopathogens fungus, Metarhizum anisopliae and bacterium, Pseudomonas aeuriginosa. The mortality percentages recorded after treatment of the 2 nd and 4 th instar larvae of S. littoralis with concentration 1×10 8 spore/ml of M. anisopliae were 84.28 and 75.71% after 5 days of treatment. While, LT50 were 0.81 and 1.93 days for 2 nd and 4 th instar larvae of S. littoralis, respectively. P. aeruginosa concentration 2.3× 10 8 spore/ml caused mortality 81.42 and 60% and LT50 3.87 and 4.51 days for 2 nd and 4 th instar larvae of S. littoralis, respectively. Pupae of S. littoralis were susceptible for both entomopathogens agents. Moreover adults emergence percentage decreased. Combined treatment of pesticides with P. aeruginosa and M. anisopliae proved best action causing higher mortality percentages for larvae compared with using pesticides alone.

Efficacy of Two Entomopathogenic Fungi in Combination with Diatomaceous Earth Against Spodoptera littoralis (Boisd.) (Lepidoptera: Noctuidae)

“…Lotfy et al (2016) observed positive influences on the 2 nd and 4 th instar larvae of S. littoralis treated with spores of M. anisopliae at different concentrations in laboratory conditions. In other studies, it was found that Metarhizium brunneum was very effective against S. littoralis and can be considered as a potential biological control agent against S. littoralis larvae (Funda and Yusuf, 2021;Eleawa et al, 2022).…”