Six species of entomopathogenic nematodes (EPNs) (Steinernema feltiae, S. carpocapsae and Heterorhabditis
bacteriophora) isolated from Turkey [S. feltiae (Aydin isolate), S. carpocapsae (Black sea isolate), H. bacteriophora
(Aydin isolate) and H. bacteriophora (Çanakkale isolate)] and from Kyrgyzstan [S. feltiae(KG3) and H.
bacteriophora (KG81)] were tested for the control of black timber bark beetle, Xylosandrus germanus (Blandford)
(Coleoptera: Curculionidae: Scolytinae) under laboratory conditions. The studies were conducted in June, 2017 at
the Ondokuz Mayıs University (Samsun, Turkey). The suspensions of nematodes were applied at one concentration
(1000 IJs ml-1) (200 IJs insect-1 or approximately 15 IJs cm-2) at 25°C temperatures. The data for mortality was
recorded after 2, 4, 6 and 8 days intervals. Insect mortality of the adult was higher in all nematode treatments than
the control. Turkish EPN isolate S. carpocapsae (Black sea) and Kyrgyz EPN isolate S. feltiae (KG3) species
showed the highest mortality (98.66%).