The impact of minimised (MIN - no plough, direct drilling, no pesticides) and standard (STN - plough, standard application of pesticides) cropping systems on the abundance of old (previously overwintered) and new generations of Meligethes aeneus (Fabricius) (Nitidulidae, Coleoptera) was assessed in spring oilseed rape in 2003 - 2005 in Estonia.  Old generation M. aeneus were more abundant in STN than in MIN crops, despite the application of insecticide, probably because the latter reduced M. aeneus damage to the buds, making STN crops more attractive to M. aeneus seeking feeding and oviposition resources.  The abundance of new generation M. aeneus showed a strong linear increase over the 3 years, on both MIN and STN systems.  In 2005, the abundance of new generation M. aeneus was significantly greater in the STN than in the MIN field.  The study showed that the application of insecticides promotes population increase in new generation M. aeneus.