Effectiveness of Selected Entomopathogenic Fungi against the Tobacco Caterpillar, Spodoptera Litura (Fabricius) (Lepidoptera: Noctuidae)

Abstract

Tobacco caterpillar, Spodoptera litura is destructive pest causes severe losses to various crops worldwide. The potential of different entomopathogenic fungi (EPFs) against S. litura was conducted at Institute of Plant Protection, MNS-University of Agriculture, Multan by using leaf dip method. Larvae and eggs were the most susceptible while pupae were less susceptible to the tested entomopathogenic fungal isolates. The early instar larvae were highly susceptible to EPFs as compared to the later instar larvae. The median lethal concentration (LC50) values for third instar larvae were 1.13×107 conidia ml-1 and 2.16×107 conidia ml-1 for B. bassiana 25 and I. fumosorosea 32, respectively. The entomopathogenic fungi pathogenicity was increased with increase in conidial concentration and mortality rate also increased. Median lethal time (LT50) of S. litura was increased with decreased in fungus conidial concentrations. The median lethal concentration (LC50) values for eggs were 1.22×106, 2.33×107 and 4.91×106 in Metarhizium anisopliae L6, Beauveria bassiana 25 and Isaria fumosorosea 32, respectively. During the study, no significant effect was recorded on adult emergence while the virulence potential of I. fumosorosea had significant impact on pupal formation. Key words: Armyworm, Entomopathogens, Pathogenicity, Biological Control