02884nas a2200181   4500008004100000020001400041245017900055210006900234260000800303300002200311490000700333520212700340653002102467100002802488700002402516700002702540856013502567       2012                        eng d  a1049-964400aThe impact of entomopathogenic nematodes on a non-target, service-providing longhorn beetle is limited by targeted application when controlling forestry pest Hylobius abietis0 aimpact of entomopathogenic nematodes on a nontarget serviceprovi  cSep  aNIL_0059-NIL_00680 v623 aEntomopathogenic nematodes are being applied to tree stumps on coniferous clearfell sites in Europe for inundative biological control of the large pine weevil (Hylobius abietis; Coleoptera: Curculionidae), a major forestry pest. We investigated the risk that two nematode species, Steinernema carpocapsae and Heterorhabditis downesi (Nematoda: Rhabditidae), present to longhorn beetle Rhagium bifasciatum (Coleoptera: Cerambycidae), a service-providing, non-target saproxylic insect on clearfell sites. In a Petri dish assay, larvae of R. bifasciatum were less susceptible (LC50 24-42) than pupae or adults (LC50 <= 10) to infective juveniles (IJs) of S. carpocapsae and H. downesi. S. carpocapsae and H. downesi reproduced within R. bifasciatum larvae, pupae and adults, with up to 130,000 IJs emerging per insect. When we applied 1.8 million IJs (half the number recommended per tree stump containing pine weevil) to deadwood logs in laboratory and field experiments, both nematode species infected more than 50% of R. bifasciatum within the logs. Field application at a lower, more realistic rate (18,000 IJs per log) resulted in 0-11% infection. The two nematode species caused similar rates of infection within logs and infected R. bifasciatum larvae more than 4 cm deep within the wood. On six clearfell sites sampled one to twelve months after S. carpocapsae had been inundatively applied to tree stumps for suppression of pine weevil, < 10% of deadwood logs contained infected R. bifasciatum and < 4% of 1989 R. bifasciatum individuals in logs were infected. Infection was recorded a year after nematodes had been applied, however, suggesting that nematodes were recycling within logs in the field. Incidence of R. bifasciatum infection decreased significantly with increasing distance between a log and the nearest treated tree stump. Thus, our results indicate that entomopathogenic nematodes can infect and recycle in R. bifasciatum, but that the risk to this and other saproxylic non-target insects is limited by the targeted application of nematodes to tree stumps. (C) 2012 Elsevier Inc. All rights reserved.10aHylobius abietis1 aHarvey, Christopher, D.1 aAlameen, Khalil, M.1 aGriffin, Christine, T.  uhttps://weevil.myspecies.info/impact-entomopathogenic-nematodes-non-target-service-providing-longhorn-beetle-limited-targeted-appl