Pollen beetle (Meligethes spp.) is a major yield-limiting factor in organic oilseed
production. Currently there are no effective methods available to control this beetle in
organic agriculture. From 2006 to 2008 work was carried out at Agroscope ARTReckenholz
to find suitable organically compatible plant protecting agents which are
effective against the beetle. A partial reduction in beetle infestation was observed
when liquid manure, lavender oil and rapeseed oil was applied. Dusting agents such
as ash and substances containing silicate (stone meal) were very efficient, almost
completely removing the beetle after application. However, beetle infestation
increased again after one or two days following application. Dusting substances in
combination with pine oil and rapeseed oil produced the best results with an effective
period of action of up to five days. The addition of vegetable oil is assumed to improve
the adhesiveness of these agents. None of the methods showed any significant
effects on oilseed yield. Practical use will require further tests and investigations into
economic feasibility and application technology
