Proactive evaluation of a native European parasitoid, Anastatus bifasciatus (Hymenoptera: Eupelmidae), for biological control of Lycorma delicatula (Hemiptera: Fulgoridae)

Abstract

Lycorma delicatula (Hemiptera: Fulgoridae) is an emerging paninvasive species native to Asia, that poses a significant threat to agriculture, urban, and natural areas worldwide. Invasive populations of L. delicatula can cause substantial damage to vineyards, and ecological niche modeling identified Europe, where viticulture is a significant industry, as an area at high-risk of future establishment. However, despite the anticipated invasion of Europe, no research has yet explored potential natural enemies of L. delicatula that could be suitable for use in Europe. The native European egg parasitoid, Anastatus bifasciatus (Hymenoptera: Eupelmidae), already used for biological control of invasive populations of Halyomorpha halys (Hemiptera: Pentatomidae) in Europe, may be a suitable candidate natural enemy for L. delicatula. This study investigated the ability of A. bifasciatus to parasitize, reproduce on, and induce mortality of L. delicatula egg masses. Results from quarantine laboratory experiments indicated that A. bifasciatus significantly increased mortality of L. delicatula eggs, even though this parasitoid was unable to complete development on L. delicatula eggs. Host feeding on L. delicatula eggs by adult female A. bifasciatus and incomplete development of parasitoid larvae within host eggs are proposed mechanisms for increased mortality of L. delicatula eggs. Moreover, non-target host range testing on native North American species confirmed that A. bifasciatus is a generalist egg parasitoid and is likely unsuitable for introduction into areas outside its native range.