Can the western conifer seed bug Leptoglossus occidentalis (Heidemann, 1910) threaten coniferous forests in Poland?

Iwona Adamska, Magdalena Dzięgielewska



This is a review article. It discusses the current state of knowledge of the biology of Leptoglossus occidentalis (Heidemann, 1910) [Hemiptera: Heteroptera: Coreidae], direct and indirect damage caused by the pest, the dangers of its rapid expansion and possible biological control. The paper presents new reports of L. occidentalis in Poland (Szczecin, north-west Poland). This pest shows great ecological flexibility, has adapted well to the climatic conditions prevailing in Europe and is spreading rapidly across the continent. The rate of its expansion is also influenced by a wide range of potential host plants that also occur in Poland at natural sites and in artificial afforestations. Due to the type and scale of damage caused by L. occidentalis, its fast reproduction rate and possibly severe losses in forest management, potential feeding grounds of L. occidentalis, such as forests in which coniferous seeds are sourced and forest nurseries, should be monitored and protected. This insect may also pose a threat to protected plant communities, for example the coastal crowberry coniferous forest (Empetro nigri-Pinetum Wojt. 1964) occurring only in north-western Poland, lichen Scots pine forest (Cladonio-Pinetum Juraszek 1927) or marshy pine forests (Vaccinio uliginosi-Pinetum Kleist 1929). Two biological agents: the egg parasitoid Gryon pennsylvanicum (Hymenoptera: Scelionidae) and entomopathogenic fungi, are currently used in biological control against this pest in Europe.


Leptoglossus occidentalis; invasive alien species; pest; conifers

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