Control of the yellow stem borer, Scirpophaga incertulas by mating disruption with a PVC resin formulation of the sex pheromone of Chilo suppressalis (Lepidoptera: Pyralidae) in India

A commercially-available, hand-applied PVC resin formulation of the sex pheromone of the striped rice stem borer, Chile suppressalis (Walker) was used to control the yellow stem borer, Scirpophaga incertulas (Walker), in a 20 ha mating disruption trial in West Bengal, India, in 1992. Indirect measures of mating disruption were used to compare the pheromone-treated plot with an untreated control plot and a farmers' practice plot where a conventional pesticide control regime was practised. The results showed that the level of 'white head' damage in the pheromone-treated plot was significantly lower than that recorded in other treatment plots and that the relative percentage of the larvae of the two major stem borer species, S. incertulas and Chile polychrysa (Meyrick) found in the region changed from 88% S. incertulas in the farmers' practice plot to 65% in the pheromone-treated plot. The yields of grain and straw recorded in the pheromone-treated plot were significantly higher than in the untreated control plot but not significantly different from those recorded in the farmers' practice plot.