EVALUATION OF 1-OCTEN-3-OL AND NONANAL AS ADJUVANTS FOR AGGREGATION PHEROMONES FOR 3 SPECIES OF CUCUJID BEETLES (COLEOPTERA, CUCUJIDAE)

1-Octen-3-ol and nonanal were evaluated as adjuvants for the aggregati on pheromones (cucujolides) of the merchant grain beetle, Oryzaephilus mercator (Fauvel), the rusty grain beetle, Cryptolestes ferrugineus ( Stephens), and the flat grain beetle, C. pusillus (Schonherr). Experim ental stimuli were tested alone and in mixtures at up to five differen t doses in corrugated cardboard traps placed on a wooden arena. Six hu ndred beetles of either sex and mixed age were tested in each experime nt. Significant responses occurred to the cucujolides 1-octen-3-ol or nonanal at one or more doses for each species, indicating that nonanal or 1-octen-3-ol could be used to replace the expensive cucujolides in some instances for monitoring purposes. The responses of 0. mercator and C. ferrugineus to their cucujolide pheromones were higher than to 1-octen-3-ol or nonanal alone, but C. pusillus responded equally to no nanal and the cucujolides. No synergism occurred between the cucujolid es and either 1-octen-3-ol or nonanal for any species, but C. ferrugin eus responded at significantly greater levels in some experiments to t he combined stimuli than to the cucujolides alone. If used in multispe cies baits to increase the efficacy of pheromones for other species, e .g., Oryzaephilus surinamensis (L.), 1-octen-3-ol or nonanal used at a ppropriate release rates should not affect the response of O. mercator , C. ferrugineus, or C. pusillus to their own pheromones.