Efficacy of insecticides against the Rice Stem-borer,Chilo suppressalis (Walker) (Lepidoptera: Crambidae), and use of sex pheromones to time accurately the yearly application

Larvae of the Rice Stem-borer, Chilo suppressalis (Walker), cause extensive crop losses worldwide. Since pesticide application is the major management tactic in China, judicious timing of a minimal dose of insecticides is important in developing an IPM program for that pest. Pheromone trap captures of male moths were used to time the single insecticide application in two seasons (2010 and 2011). In 2010, six pesticides – deltamethrin, cygon, chlorpyrifos, cartap, fipronil, and esfenvalerate – gave >90% control of stem-borers, and reduced damage to less than 5.0%. In 2011, control exceeding 90% and a damage level of <5.0% and was achieved with 0.35 kg/ha deltamethrin and chlorpyrifos. Cygon, at either 0.30 or 0.35 kg/ha, provided control exceeding 90% and a damage level of <4.0%. With the proviso that the impact of insecticides on biological control agents remains to be investigated, these three insecticides are recommended for use by Chinese rice farmers.