Pathogenicity of Native Entomopathogenic Fungus Nomuraea rileyi Against Spodoptera litura

Abstract

The entomopathogenic fungus Nomuraea rileyi was isolated from Spodoptera litura and Helicoverpa armigera insect cadavers collected from different sampling sites. Pathogenicity of ten N. rileyi isolates against Spodoptera litura was studied by exposing third instars to topical application of a spore concentration of 10 8 conidia/ml. All ten isolates of N rileyi were active against third instars of S. litura, resulting in 85 to 97% mortality. However, there were statistically no significant differences among the isolates with respect to the pathogenicity levels. Median lethal time (LT 50 ) values of N. rileyi isolates against third instars of S. litura ranged from 5.5 to 6.6 days, which were not statistically different. This strongly suggests that the isolates from different geographical locations are equally pathogenic against S. litura.

Evaluation of <i>Metarhizium (Nomuraea) rileyi</i> (Farlow) Samson isolates against <i>Spodoptera litura</i> F. under <i>in vitro</i> conditions

“…Krutmuang and Thungrabeab (2017) tested eight strains of M. rileyi for control of S. litura and recorded the larval mortality ranged from 2.5 to 92.5% at 7 days after inoculation and documented two strains, BCC 14653 and BCC 14671 as highly virulent. Padanad and Krishnaraj (2009) isolated entomopathogenic fungus M. rileyi from S. litura and H. armigera insect cadavers collected from different sampling sites and evaluated its pathogenicity against S. litura by topical application of 10 8 conidia/ml concentration suspension. All ten isolates of M. rileyi were active against third instar S.litura, resulting in 85 to 97% mortality.…”

Natural Enemies of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae), a Recent Invasive Pest on Maize in South India

“…For instance, Telenomus remus Nixon (Hymenoptera: Platygastridae), an effective egg parasitoid of S. litura, is known to parasitize S. frugiperda as well (Molina-Ochoa et al 2003). Nomuraea rileyi was found to be very effective against S. litura (Padanad & Krishnaraj 2009) in Karnataka.…”