Monitoring flight activity of Cryptolestes ferrugineus (Coleoptera: Laemophloeidae) in outdoor environments using a commercial pheromone lure and the kairomone 1-octen-3-ol

Abstract

Abstract Effective trapping techniques for Cryptolestes ferrugineus are essential for developing an understanding of the ecology of this beetle outside the storage environment, and will assist in monitoring the spread of fumigant resistance in field populations. We evaluated ten different volatile compounds associated with stored grains or fungi as potential attractants for C.\xa0ferrugineus using Lindgren funnel traps fitted with glass dispenser tubes. Only two compounds, 1-octen-3-ol and 3-octanone, were effective attractants in outdoor environments. Beetle captures increased with increasing release rates of both compounds. 1-octen-3-ol was the most effective attractant, and we evaluated it in conjunction with a commercial rubber septum lure containing the two macrocyclic lactones that constitute the C.\xa0ferrugineus aggregation pheromone. In parallel trials the commercial lure performed poorly, catching only 2% of the wild beetles recovered. 1-octen-3-ol deployed alone caught 26% of beetles, however a combination treatment (pheromone lure\xa0+\xa01-octen-3-ol) accounted for 72% of C.\xa0ferrugineus captures, suggesting a synergistic interaction. Evaluation of rubber septa impregnated with 1-octen-3-ol demonstrated that these were just as effective as glass release tubes when deployed with the pheromone lure over a five day period. A comparison of different trap types using the pheromone lure/1-octen-3-ol combined attractants showed that significantly more C.\xa0ferrugineus were captured with a panel trap than with either 4-unit or 9-unit Lindgren funnel traps, correlating to the much higher rate of 1-octen-3-ol volatilisation from the panel trap. A funnel trap fitted with a 1-octen-3-ol dispenser was used to continuously monitor C.\xa0ferrugineus flight activity for a three year period and captured 4335 individuals, demonstrating that although optimum catches are obtained using the pheromone/1-octen-3-ol combination, 1-octen-3-ol can be used alone to monitor the seasonal flight activity of C.\xa0ferrugineus.