The female sex pheromones of Chilo suppressalis (Wlk.) were previously identified as (Z)-11-hexadecenal and (Z)-13-octadecenal. This paper describes field trials of the synthetic pheromones carried out in the Philippines, Korea and Iran during 1975 and 1976. These trials established that the two pheromones in their naturally occurring ratio are attractive to male C. suppressalis in the field. Both pheromones are necessary for efficient attraction, and ratios of the two pheromones close to the naturally occurring ratio are the most attractive. The rate of release of the pheromones was found to be critical in order to obtain an attractant source comparable with the virgin female moth. The bisulphite adducts of the pheromones showed some promise as a slow-release source of attractant material with a long field life.
Preliminary experiments were carried out to assess the potential use of the two natural pheromones and of two pheromone “mimics”. (Z)-9-tetradecenyl formate and (Z)-11-hexadecenyl formate, as mating disruptants. All four compounds were shown to interfere with pheromonal communication between the sexes