The lackey moth, Malacosoma neustria (Linnaeus, 1758), a worldwide pest, causes extensive economic losses on particularly hazelnut, Prunus, Quercus, Populus, and Salix trees. In this study, a local nucleopolyhedrovirus (NPV) was isolated from the larvae of M. neustria in the northeast of Turkey. | Turkish Journal of Biology Turk J Biol (2013) 37: 385-391 © TÜBİTAK doi: Research Article Characterization of a new isolate of Malacosoma neustria nucleopolyhedrovirus (ManeNPV) from Turkey 1, 1 1,2 İsmail DEMİR *, Remziye NALÇACIOĞLU , Lida MOHAMMAD GHOLİZAD , Zihni DEMİRBAĞ 1 Department of Biology, Faculty of Sciences, Karadeniz Technical University, 61080 Trabzon, Turkey 2 Department of Biology, Faculty of Sciences, Urmia University, Urmia, Iran Received: Accepted: Published Online: 1 Printed: Abstract: The lackey moth, Malacosoma neustria (Linnaeus, 1758), a worldwide pest, causes extensive economic losses on particularly hazelnut, Prunus, Quercus, Populus, and Salix trees. In this study, a local nucleopolyhedrovirus (NPV) was isolated from the larvae of M. neustria in the northeast of Turkey. It was named ManeNPV-T2. Electron microscopic observations showed that the polyhedra of the new isolate contain several virions with multiple nucleocapsids packaged within a single viral envelope. Restriction endonuclease analysis of ManeNPV-T2 DNA indicated that it has a different restriction profile compared to the previous Turkish and Latvian isolates. The phylogenetic analysis of the amplified polh sequence of ManeNPV-T2 showed its relation to the other NPVs from Malacosoma species. Mortality values for third instar M. neustria larvae ranged from 48% to 100% according to the concentration of polyhedral occlusion bodies. Based on screening tests, the LD50 value of the new isolate was calculated as × 104 occlusion bodies per larvae. Consequently, ManeNPV appears to be a promising microbial control agent for biocontrol of M. neustria. Key words: Malacosoma neustria, nucleopolyhedrovirus, characterization, ManeNPV, insect virus 1. Introduction Baculoviruses are enveloped viruses that have doublestranded, circular DNA genomes ranging in size from 80 to .