Ausbreitung des Rapsglanzkäfers innerhalb eines Feldes und in der Landschaft

Summary

Pollen beetles (Meligethes sp.) are important pests in oilseed rape (Brassica napus). In
our study we wanted to determine which landscape structures have an influence on pollen beetle
population in early spring. The dynamics of pollen beetle population and the damages on rape were
studied on field scale level with 100 sampling points per field and on landscape scale level with 18
organic oilseed rape fields which differed by the complexity of the surrounding landscapes. The
number of pollen beetle was strongly correlated with the distance to a forest. At the beginning of
the flight period more pollen beetles were found close to the forest, later they migrated to the rest of
the field. In addition, agricultural practices appeared to be determinant for pest control. Less pollen
beetles per plant were found in fields with a higher density of rape plants.