A comparison of the efficiency of kairomone lures for Bruchus rufimanus monitoring

The bruchid beetle Bruchus rufimanus Boh. is a common pest in Europe affecting grain quality of faba bean Vicia faba L. and reducing its marketability. The control of this pest in Europe mainly relies on spraying pyrethroid insecticides in the field. However, because of its biology and low sensitivity to pyrethroid the control of this pest remains challenging. New control methods need to rely on integrated pest management programs (IPM). Semiochemical traps appear as a promising IPM tool by providing monitoring information, but also by its potential use as a mass-trapping control method. In this study, the attractiveness of four semiochemical treatments (two floral kairomones, one pod kairomone and both floral and pod kairomones just in sequence) associated with two types of traps (sticky card and water pan traps) was evaluated in three Irish faba bean crops, aiming to provide evidence-based advice for the selection of semiochemical trapping methods and development of IPM programs. Our results highlight the efficiency of a floral kairomone to attract B. rufimanus in the field. While associated with higher B. rufimanus catches the water pan trap caught a significant number of bees. In addition, no semiochemical differences between treatments were observed in terms of earliness of the capture and sex-ratio. To optimise the number of bruchid catches and reduce non-target pollinator capture, floral kairomone combined with sticky traps were considered as the most promising combination for monitoring and mass-trapping.