Distribution and identification of cereal leaf beetles in Flanders
Cereal leaf beetles, a genus of leaf beetles (Coleoptera: Chrysomelidae – Oulema spp.) are known pest species of cereals in the Northern hemisphere. Due to very small differences in morphology, accurate identification of the species within this genus is still a challenge. Moreover, since these species exhibit a different phenology and thus the date of control practices is dependent on the dominant species, it is important to know what species make up most of the population. By this, more selective control strategies can be developed in the future without using too much pesticides.
BINCO collaborated with a study on the distribution and species diversity of cereal leaf beetles in Flanders. The species diversity was monitored in several cereal fields during three executive years. We found three species of Oulema which were frequently present; O. melanopus, O. duftschmidi and O. obscura. By the use of discriminant analysis, we found that these species can be identified quite reliably by body shape (like length and width of elytra), but checking the identifications by use of genital structures is still advisable.
Population densities were very variable within and between years, which could hamper selective control strategies. This would require an adequately big and spatially and temporally spread sampling campaign.
The results of this project were published in the scientific journal Environmental Entomology and can be found here.
Photo: Hilde Christiaens, this project was funded by VLAIO-LA