Is pre-emptive classical biological control feasible for Aleurocanthus woglumi in Europe?

• The citrus blackfly, Aleurocanthus woglumi is an imminent threat for the European citrus industry. • Classical biological control has been historically successful against A. woglumi in invaded areas with introduced hymenopteran parasitoids. • Two parasitoid species, Encarsia perplexa and Amitus hesperidum , have been used worldwide for the biological control of Aleurocanthus woglumi. • Evidence suggests that pre-emptive biological control for Aleurocanthus woglumi in Europe is feasible and would mitigate the impact of an introduction. Citrus blackfly, Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae) is a major pest of Citrus spp that originated from south-east Asia and spread in many tropical and subtropical regions of the world. Citrus blackfly has not yet dispersed either in the Mediterranean basin or in Europe where it could become a devastating pest for citrus crops in these areas. It is a regulated quarantine species for the EU. Successful classical biological control programs were implemented in the past in areas invaded by A. woglumi . Therefore, potential biocontrol agents have been identified and could be used for classical biological control in newly invaded areas. European citrus is threatened by the potential introduction of A. woglumi and classical biological control would be an effective mitigation measure should an incursion occurs. With classical biological control programs being notoriously delayed due to necessary risk assessments, the concept of pre-emptive biological control prior to the introduction of an invasive pest enables the deployment of management strategies prior the pest’s introductory phase to enable elimination and/or minimization of its impact on the invaded area. Following specific guidelines that recently became available, we assess the feasibility of pre-emptive biological control for A. woglumi , taking into account the particular characteristics of European agriculture. We focus on two parasitoid species that have been successfully used in the past for classical biological control programs against A. woglumi in other parts of the world. We conclude that pre-emptive biological control for A. woglumi is feasible and citrus industries in Europe and the Mediterranean basin would benefit from it should the introduction of A. woglumi occur.