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Malacosoma neustria (Linnaeus, 1758) (Lepidoptera: Lasiocampidae) causes economic losses in apple, pear, plum, willow, oak and other economically important trees. In this study, an alphabaculovirus was isolated from the larval population of M. neustria from Samsun in the central Black Sea Region of Turkey between 2015 and 2016. Electron microscope analysis of occlusion bodies (OBs) obtained from dead larvae showed that the nucleocapsids of a new isolate (ManeNPV-T4) are multiply enveloped. The Kimura two-parameter analysis and the phylogenetic tree were performed based on concatenated nucleotide and amino acid sequences of the partial lef-8, lef-9 and polh genes from ManeNPV-T4 isolate compared to those of other 51 baculoviruses. Insecticidal activity tests against third instar M. neustria larvae produced 48 to 100% mortalities. The LC 50 of ManeNPV-T4 was 0.78 x 10 3 OBs/ml in M. neustria . Additionally, the isolate caused mortalities lower than 50% in Spodoptera exigua (Hubner, 1808) (Lepidoptera: Noctuidae) , Lymantria dispar (Linnaeus, 1758) (Lepidoptera: Erebidae) , Hyphantria cunea (Drury, 1773) (Lepidoptera: Arctiidae) and Helicoverpa armigera (Hubner, 1805) (Lepidoptera: Noctuidae) larvae. Consequently, the new nucleopolyhedrovirus is infectious on M. neustria larvae and other lepidopterans.

A nucleopolyhedrovirus (NPV) was isolated from diseased larvae of the eastern tent caterpillar, Malacosoma americanum (Fabricius), collected from the northeastern part of Turkey. Light and electron microscopic observations showed that this virus is a multiple nucleopolyhedrovirus (MNPV). The dimensions of the polyhedral inclusion bodies varied from 1.0 to 2.1 µm, and the sizes of the virions were also measured to be approximately 194.5 nm. Restriction analysis of the new isolate and ManeNPV-T2 (previously isolated from M. neustria larvae) showed that the new virus is closely related to ManeNPV-T2. Furthermore, sequence and phylogenetic analysis of polh and lef-8 also revealed a high degree of homology to M. neustria NPV. Our results indicate that the new virus is another isolate of ManeNPV that infects M. americanum larvae naturally. Therefore, it was named ManeNPV-T3. The virulence of ManeNPV-T3, which was tested against the third instar of M. americanum and M. neustria larvae under laboratory conditions, indicated that 0.6 × 105 occlusion bodies per larvae caused 100% mortality within 10 days. The same dose also showed viral infection in Malacosoma castrensis, Plodia interpunctella, Thaumetopoea pityocampa, and Galleria mellonella larvae causing 65%, 60%, 35%, and 25% mortalities, respectively. The findings indicate that ManeNPV-T3 is a promising microbial agent for the biological control of Malacosoma species.

Three genes encoding chitinase A (chiA), B (chiB), and C (chiC) were amplified from a bacterium that was isolated from a naturally dead Helicoverpa armigera larva and identified as Serratia marcescens based on 16S rRNA gene sequence analysis (KF823633 accession number). The open reading frames (ORFs) were identified as 1692, 1500, and 1443 base pairs for chiA, chiB, and chiC genes, respectively. These sequences were submitted to the GenBank with accession numbers KF823630 (chiA), KF823631 (chiB), and KF823632 (chiC). Comparison of the deduced amino acid sequences with those of other bacterial chitinases revealed that the 3 chitinases contain the catalytic domain. Furthermore, all 3 chitinases showed 99% similarity to the S. marcescens WW4 strain at the amino acid level. The chitinases were overexpressed in Escherichia coli. Expressed proteins were purified and their activities were tested using colloidal chitin as substrate. Reasonable pH and temperature ranges were also determined as 7-11 and 33-37 °C, respectively. Insecticidal activities of these proteins were tested on the larvae of Malacosoma neustria and H. armigera. Test results showed that 1000 U/mL ChiA, ChiB, and ChiC have 47%, 50%, and 66% insecticidal activities on M. neustria, and 80%, 45%, and 50% insecticidal activities on H. armigera larvae within 10 days, respectively.

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 1.34 × 104 occlusion bodies per larvae. Consequently, ManeNPV appears to be a promising microbial control agent for biocontrol of M. neustria.

Nalcacioglu, Remziye/0000-0003-0527-9541; Demirbag, Zihni/0000-0001-5487-1977; INCE, Ikbal Agah/0000-0003-2299-9946 WOS: 000271434700009 A plaque-purified genotypic variant, derived from a field isolate of the Malacosoma neustria nucleopolyhedrovirus (ManeNPV) from Turkey was characterized based oil in vitro replication properties in a cell line, Md203 derived from Malacosoma disstria. The life cycle of ManeNPV was studied based oil the cytopathic effects (CPEs), polyhedral inclusion body (FIB) formation, budded virus (BV) production, viral DNA replication and polyhedrin protein expression in ManeNPV-infected Md203 cells. Infection of Md203 cells with ManeNPV resulted in cytopathic effects within 24 and 36 h post infection and most cells detachted from the bottom of the culture plate oil the fourth day. Typical NPV cytopathic effects (CPE) like granulated and rounded cells, nuclear hypertrophy and impairment in cell proliferation, and lost cell shape with the extendings were observed. Budded viruses were detected at 24 h p.i. However, significant increase in BV production was observed after 48 h p.i. PIB was firstly detected at 36 h p.i. When BV's were used for reinfection of the Md203 cells, the result showed that these cells support production of viable virus progeny. We also observed a significant level of viral DNA synthesis by 24 h p.i. The results indicate that ManeNPV can be propagated at in vitro system for further studies and thus has a potential for development into an effective biotechnological and microbial insecticidal agent. Karadeniz Technical University Research Foundation [KTU 2007.111.004.11] This study was supported by the Karadeniz Technical University Research Foundation (KTU 2007.111.004.11). We are thankful to Dr. Keddie (Department of Biological Science, University of Alberta, Edmonton, AB T6G 2E9, Canada) for providing us with a flask of Md203