Differences in colour preference among pollen beetle species (Coleoptera: Nitidulidae)

Pollen beetles (Coleoptera: Nitidulidae) are major pests of oilseed rape and other crucifers. Efficient and timely management of these pests can greatly be improved by effective monitoring of their spatial and temporal distribution. In field trials in Hungary, we have discovered striking differences in colour responsiveness among pollen beetle species: Brassicogethes aeneus F. 1775 (earlier Meligethes aeneus) and B. viridescens F. 1775 responded most strongly to fluorescent yellow traps, whereas B. coracinus Sturm 1845, Fabogethes nigrescens Sturm 1845 and Meligethes atratus Olivier 1790 were most attracted to blue or white traps. Differences in the spring flight period were also recorded, with B. aeneus and B. viridescens flying ca. 1 month earlier than the other three species. Further tests established that funnel traps having both fluorescent yellow and blue colour cues are the most efficient in attracting a wide range of pollen beetle species. On the other hand, fluorescent yellow traps can be used to detect and monitor B. aeneus specifically.