Virulence of entomopathogenic nematode isolate Steinernema bicornutum against diamondback moth (Plutella xylostella L.)

Abstract

Plutella xylostella L., commonly known as the diamondback moth, is a significant pest of cole crops. It has established resistance to a range of pesticides, including chemical insecticides and Bt toxins. The use of appropriate bio-agents to manage the diamondback moth is a viable alternative to chemical pesticides. The current study was carried out with the goal of using entomopathogenic nematode (EPN) isolate Steinernema bicornutum to manage diamondback moths. Laboratory studies were carried out to know the virulence and reproductive potential of an indigenous population of Steinernema bicornutum at five doses i.e., 2IJs, 5 IJs, 8 IJs, 10 IJs and 12 IJs per third instar larvae of diamondback moth. Percent mortalities were recorded after 24h, 48h and 72h of post inoculation. Maximum percent mortality (81.25) was recorded after 72h with the highest dose i.e., 12 IJs per larva and the LC50 value was 7.99 IJs/100µl. The result of reproduction and recovery of isolates of entomopathogenic nematodes revealed that the highest IJs was yielded (2255.7) from dose of 12 IJs/larva. The overall results strongly suggested that P. xylostella is more susceptible to the entomopathogenic nematode and can be the host for multiplication of entomopathogenic nematodes under laboratory conditions.