Rhabditis sp (Oscheius sp), A Biocontrol Agent Against Rice Yellow Stem Borer, Scirpophaga incertulas

Experiments were carried out to study the efficacy of an entomopathogenic nematode (EPN), Rhabditis (Oscheius) sp. against yellow stem borer (YSB), Scirpophaga incertulas in rice. The effect of EPN on egg mass and field collected larval populations of the stem borer was investigated under greenhouse and laboratory conditions. Infection by the EPNs resulted in mortality of the egg mass and the neonate larvae that emerged from the eggs. The EPN was more effective in the dry season than in the wet season on the field collected larvae. The time taken for larval mortality of YSB and the multiplication rate of the nematode was inversely correlated with the dose in the dry season. Inoculation of Rhabditis (Oscheius) sp. with the stem dip method was more effective than with filter paper impregnation technique. Spray application of EPN (at 2000 IJs/pot) to potted plants pinned with YSB egg mass in the greenhouse resulted in lower dead heart damage.