Intraspecific variability of Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) as biological control agent of rice weevil (Sitophilus oryzae [L.], Coleoptera, Curculionidae) adults

The efficacy of three strains (B30, B49 in 3162) of Steinernema feltiae to control adults of rice weevil (Sitophilus oryzae) was tested in a laboratory experiment in 2009. The activity of entomopathogenic nematodes was assessed at five different concentrations (125, 250, 500, 1000 and 2000 infective juveniles/individual) and four different temperatures (15, 20, 25 and 30 °C). Results demonstrated that all strains acted most effective at 25 °C and at highest concentration of nematode suspension, meanwhile the lowest mortality of rice weevil adults was attained at 30 °C. The results of our research showed that at high concentrations entomopathogenic nematodes are an effective biological agent for controling the studied primary stored products pest.