Interpreting the host range of Peristenus digoneutis and Peristenus relictus (Hymenoptera: Braconidae) biological control agents of Lygus spp. (Hemiptera: Miridae) in North America

A study of the European parasitoids Peristenus digoneutis and Peristenus relictus, introduced for the biological control of Lygus lineolaris and Lygus hesperus, was conducted to determine their potential host ranges in North America. No-choice laboratory tests suggested that native Lygus spp. were equally likely to be hosts of both parasitoids. Other non-target Miridae were not suitable hosts for P. digoneutis but Amblytylus nasutus, Leptopterna dolabrata and Melanotrichus coagulatus may be suitable for development of P. relictus. Comparison with field data in North America and studies in Europe suggest that non-target Lygus spp. may be impacted by P. digoneutis while other non-target species would not. In contrast, the nontarget Lygus spp. and at least several other non-target mirid species are likely to be impacted by P. relictus. Potential impact on non-target Lygus spp. would be highest in the Western North American bioregion where the greatest number of native species occurs. In the Eastern North American bioregion where the Lygus fauna consists of fewer, mainly widespread species, impacts on non-target Lygus spp. are expected to be minimal. It is recommended that post-release surveys be conducted to quantify potential impacts on non-target Lygus spp. Crown Copyright (C) 2011 Published by Elsevier Inc. All rights reserved.