Situation of <i>Lymantria dispar</i> in Europe

Abstract

The situation of Lymantria dispar in Europe and Russia was reviewed at an EPPO meeting held in Poznan (PL) in 1995‐03. The introduction of an Asian form of L. dispar , with flying females and a wider host range, from the Far East of Russia across the Pacific Ocean into North America had led to concerns that such a form might be present elsewhere in the EPPO region and might be introduced into North America across the Atlantic Ocean. Outbreaks of L. dispar were observed in many parts of Western Europe in the early 1990s, but were not considered exceptional compared with earlier outbreaks. Flying females were, however, seen in Germany. Preliminary results obtained with DNA markers suggested that the ‘Asian genes’ which they identify occur at low density in Western Europe, and that there is a progressive eastwards increase in their frequency. It is concluded that the presence of ‘Asian genes’ and of flying females, at low density, is a normal feature of European populations of L. dispar , and that European countries do not need to take special measures against the introduction of an ‘Asian form’.