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The apple maggot, Rhagoletis pomonella(Walsh) (Diptera: Tephritidae), is considered a key pest of apples and is native to the eastern United States. The virulence of seven different species of entomopathogenic nematodes (EPN) was assessed against pupae of R. pomonellaunder laboratory conditions. Nematode species and strains included Steinernema carpocapsae(ALL strain), Steinernema feltiae(SN strain), Steinernema riobrave(355 strain), Steinernema glaseri(VS strain), Heterorhabditis bacteriophora(VS strain), Heterorhabditis indica(HOM1 strain), and Heterorhabditis megidis(UK211 strain). We conducted three bioassays: (i) short-term exposure cup bioassay (7 d), (ii) long-term cup bioassay (30 d), and (iii) pot bioassay (30 d). In the short-term exposure bioassay, all nematode strains (applied at 54 infective juvenile nematodes (IJs) cm−2) significantly reduced (range: 42.9-73.8%) insect survival relative to the control, but no differences were observed among the treatments. For the long-term exposure bioassay, using the same EPN application rate as the short exposure assay, all treatments reduced adult R. pomonellaemergence compared with the control. Steinernema riobravewas the most virulent (28.3% survival), and S. glaseriand H. megidiswere the least virulent (53.3% survival). In the pot experiment, S. riobraveand S. carpocapsae(applied at 27 IJs cm−2) had the highest virulence (23.3 and 31.7% survival of R. pomonella, respectively), while H. bacteriophorawas the least effective (68.33% survival). Our results indicate that S. riobrave, S. carpocapsae, and S. feltiaehave substantial potential to attack R. pomonellapupae, and their field application under the tree canopy (prior to adult emergence) in the spring when temperatures are conducive might be a good option for successful IPM of apple maggot fly.