Pollen Beetle

M. aenus is an important pest of oilseed rape particularly in Western Europe. The larvae are up to 3 mm long and white with brown sclerotised plates. Eggs are laid in the flower buds of the host-plant and the larvae develop within the flowers. Oviposition damage to the buds of oilseed rape can cause the flowers to drop off. Both adults and larvae feed on the pollen and nectar in the flowers.

Resistance to pyrethroids has been reported in this species since 1999. Initial reports suggest that pyrethroid resistance first occurred in North East France and over the following years has spread to other countries in Europe. Investigations into the mechanism of resistance has primarily identified enhanced metabolism by P450 monooxygenases as the prime mechanism of resistance to pyrethroids. More recently  a target site mutation has also been identified in some resistant populations from Denmark and Sweden.

Pollen Beetle resistance profile

Resistance to pyrethroids has been reported in this species since 1999. Initial reports suggest that pyrethroid resistance first occurred in North East France and over the following years has spread to other countries in Europe. Investigations into the mechanism of resistance has primarily identified enhanced metabolism by P450 monooxygenases as the prime mechanism of resistance to pyrethroids. More recently a target site mutation has also been identified in some resistant populations from Denmark and Sweden.