First records of the Z-Race of European Corn Borer <em>Ostrinia nubilalis</em> (Hübner 1796) from Scandinavia

Abstract

European Corn Borer (ECB, Ostrinia nubilalis) is among the main pests of maize in Europe and throughout its intro­duced range. Two morphologically indistinguishable phero­mone races of the species exist, the so-called E-race and Z-race. In Germany the E-race is most common in mugwort (Artemisia vulgaris) whereas the Z-race occurs mainly in maize and is responsible for the main proportion of the economic damage. But both races have several alternative host plants. For example, the E-race can also occur in maize. The species has been known from Scandinavia already for a considerable time period, but no occurrence in maize was reported until recently. In 2010 larvae were found in maize at one site on the isle of Sealand, Denmark. A monitoring with Z-race pheromone traps in Denmark in 2011 did not result in any catches of ECB. In the same year however, ECB larvae were found in maize at 3 sites in southern Sweden. Larvae from 2 sites were assigned to Z-race via PCR. Independently from these finds, adult moths caught on the isle of Gotland in 2010 were also confirmed to be Z-race by PCR. This is the first evidence of the occurrence of the Z-race in Scandinavia and the northernmost find of the Z-race in Europe so far. Implications for plant protection are discussed.