Abstract
The injury of Spodoptera litura to the taro plant (Colocasia) can be prevented by masstrapping using traps baited with synthetic sex pheromone and by spraying with nuclear-poly-hedrosis virus. Mass-trapping and releasing synthetic mating disruptants did not significantly suppress the larval population density, probably because the plots used in both treatments were smaller than the flying area of adults. The experimental results suggest that successful control of S. litura population would be possible if a more extensive area were treated. The number of males captured in traps increased with an increase of the larval population density from July to August. These results indicate the feasibility of successful forecasting of the population density of this insect. The timely spraying of young larvae with nuclear-polyhedrosis virus would enable significant suppression of the population density of the larvae at 5th and 6th instars, which most injurious to the taro plant.
