Attraction of the Invasive Hornet, Vespa velutina nigrithorax, by using Bacillus sp. BV-1 Cultures

BACKGROUND: The invasive hornet Vespa velutina nigrithorax has becomes a public concern in rural and urban South Korea. The technologies are necessary to develop a way to counter V. velutina. In an effort to develop a way to counter V. velutina, we found that a bacillus strain, named Bacillus sp. BV-1, produces volatile compounds that attract V. velutina. METHODS AND RESULTS: Field trials of V. velutina attraction were performed using plates and traps containing BV-1 cultures grown on sugar medium. When the sugar medium and sugar-grown BV-1 cultures in the plates were placed close together, V. velutina visited preferably the plates with the BV-1 cultures. Significantly more V. velutina were caught in the traps containing BV-1 cultures than in those containing only sugar medium. Headspace solid-phase microextraction coupled with GC/MS analysis of BV-1 cultures detected 2-methyl-1-propanol, 3-methyl-1-butanol, 3-methylbutanoic acid, ethyl hexanoate, 2-pheylethanol, ethyl octanoate, and ethyl decanoate as the major volatiles. CONCLUSION: BV-1 cultures were suggested as potential agents for managing V. velutina as they produce volatile compounds that attract the hornet.