Trapping efficacy of different pheromone formulations on adult Maladera spp. in tobacco fields

To screen effective pheromone formulations suitable for trapping Maladera spp. adults in tobacco field, this study employed agar-gel encapsulation slow-release technology and used phenylacetaldehyde, geraniol, ethyl 2-methylbutyrate, isobutyl acetate, and benzyl acetate as active components to prepare four binary and three ternary compound pheromone attractants. By conducting systematic field trapping experiments in tobacco fields in Bijie, the trapping efficacy of different formulations was compared. The results showed that there were significant differences in trapping efficacy among different formulations, and the ternary compound formulations were overall superior to the binary ones. Among them, formulation BXY (phenylacetaldehyde : geraniol : isobutyl acetate = 3 : 1 : 1, mass ratio) exhibited the best trapping efficacy for both the total scarab beetle population and Maladera spp., and the average number of beetles trapped per single trap was 14.2 and 5.9, respectively. Formulation BYE (phenylacetaldehyde : isobutyl acetate : ethyl 2-methylbutyrate = 3 : 1 : 1) exhibited the highest specificity for Maladera verticalis, with an average of 4.1 adults trapped per trap. The ternary pheromone formulations with phenylacetaldehyde as the core component show good trapping potential for Maladera spp. adults, and formulation BXY can be promoted and applied as an ideal green control attractant for the control of Maladera spp..