Survival and infectivity of entomopathogenic nematode Heterorhabditis indica Poinar, Karunakar & David incubated in solutions containing different spray adjuvants

Abstract

We examined the survival and infectivity of the entomopathogenic nematode (EPN) Heterorhabditis indica incubated in 1, 2 and 3% solutions of three different spray adjuvants: Tween 20, Sticker 99 and Tween 80 under laboratory conditions. Infective juveniles (IJs) of H. indica were added to aqueous solutions containing each of the three adjuvants and nematode survival and infectivity were studied over time. Incubation of IJs in solutions containing the Sticker 99 resulted in consistently higher survival and infectivity compared to solutions containing Tween 20 or Tween 80. Findings indicate that tank-mixing of EPNs with Sticker 99 should not pose a significant risk to the nematodes. The influence of these adjuvants on H. indica performance in the field remains to be examined.