An alphabaculovirus isolated from dead Lymantria dispar larvae shows high genetic similarity to baculovirus previously isolated from Lymantria monacha – An example of adaptation to a new host

Abstract

A new isolate of baculovirus, Lymantria dispar multiple nucleopolyhedrovirus-BNP (LdMNPV-BNP), was found in dead gypsy moth (L. dispar) caterpillars collected in the Biebrzanski National Park in Poland. Here, we examined its biological activity, structure, genetic content and phylogeny. Multiple nucleocapsids of LdMNPV-BNP are enveloped together in 2-26 virions embedded in occluded bodies (OBs) very similar to the OBs previously described in viruses infecting Lymantriinae. This isolate kills pest larvae in a relatively short time (LT50 of approximately 9days for a dose of 2×10(7)OBs/ml), highlighting the possibility for its use as a biopesticide. Next-generation sequencing of LdMNPV-BNP revealed gene content (e.g. DNA photolyase) that is not present in any LdMNPV isolate sequenced to date. The genome is 157,270 base pairs long and has a notably lower G+C content in comparison to other LdMNPVs (50.3% G+C content compared to an average of 57.4% among other LdMNPVs). According to our phylogenetic analysis based on 37 core genes, LdMNPV-BNP is a member of group II alphabaculoviruses, which are closely related to LdMNPV and LyxyMNPV (Lymantria xylina multiple nucleopolyhedrovirus). Molecular evolution inference based on the partial sequence of lef-8, lef-9 and polh genes shows that LdMNPV-BNP and isolates of Lymantria monacha nucleopolyhedrovirus (LymoNPV) may share a very recent common ancestor or be isolates of the same virus species. LdMNPV-BNP, like other baculoviruses, could be beneficial as an active component of biopesticides that can be used during forest integrated pest management.

Molecular Alliance of Lymantria dispar Multiple Nucleopolyhedrovirus and a Short Unmodified Antisense Oligonucleotide of Its Anti-Apoptotic IAP-3 Gene: A Novel Approach for Gypsy Moth Control

“…It is known that LdMNPV is widespread among gypsy moth populations and may be transmitted transovarially [ 23 , 24 ]. Naturally occurring LdMNPV epizootics often run their course and eventually control outbreaks among populations of gypsy moths in non-recreational forested areas [ 26 ].…”

“…Our particular attention will be devoted to LdMNPV-infected larvae, a group widely distributed among gypsy moth populations [ 23 , 24 ]. Baculovirus infections in lepidopterans may cause difficulties in silencing with nucleic acids, particularly dsRNA [ 3 , 25 ].…”

Genetic Identification and Biological Characterization of Baculovirus Isolated from Helicoverpa armigera (Lepidoptera: Noctuidae) in Brazil

“…On the other hand, some reports indicated the possibility of baculovirus adapting to new hosts and causing high mortality rates (Jehle et al 2006). Rabalski et al (2016) found this to be the case when they evaluated the similarity of the alphabaculovirus isolated from dead Lymantria dispar (L.) (Lepidoptera: Lymantriidae) larvae and showed high genetic similarity to baculovirus previously isolated from Lymantria monacha (L.) (Lepidoptera: Lymantriidae).…”

Complete Genome Sequence of Lymantria dispar multiple nucleopolyhedrovirus Isolated in Southwestern Poland

“…KU377538) found in dead gypsy moth caterpillars in Biebrzanski National Park, Poland. However, this isolate shows more genetic similarities to Lymantria monacha baculovirus than any other LdMNPVs sequenced to date (2). The isolate reported in this paper and strain LdMNPV-3054 from Spain are the only two of European origin (3) for which complete genomic sequences are available.…”