Pollen beetle (Meligethes aeneus Fab) susceptibility to synthetic pyretroids – pilot study in Estonia
Institute of Agricultural and Environmental Sciences, Estonian University of Life Sciences, Kreutzwaldi 1 Tartu 51014 Estonia e-mail: firstname.lastname@example.org
Pollen beetle (Meligethes aeneus Fab) is a common pest of oilseed rape. The development of resistance to pyrethroids in M. aeneus is widespread in northern Europe. In Estonia, the majority of farmers apply insecticides against pollen beetles without considering the threshold levels of the pest. This creates good preconditions for development of resistance in M. aeneus. To date the susceptibility tests of pollen beetles have not been conducted in Estonia and it is unknown whether the local pest population has any resistance to pyrethroids. Therefore a pilot study was conducted to ascertain the state of resistance inthe Estonian pollen beetle population. Approximately 200 adult beetles were collected from two intensively managed spring oilseed rape fields in Jõgeva and Tartu County. The susceptibility test was conducted according to IRAC test method No 11, with lamda-cyhalothrin as a standard for testing the synthetic pyrethroid resistance. In 20% lamda-cyhalothrin solution the majority of insects were affected and at the normal field rate (100%) all studied insects were affected which demonstrates that they were not resistant. These results suggest that the pollen beetles are susceptible to synthetic pyrethroids in these monitored regions in Estonia. However, additional studies are necessary to make conclusions about the extent of resistance or susceptibility to pyrethroids in the Estonian beetle population.