Submitted to: Society for Invertebrate Pathology Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 4/30/2013
Publication Date: 8/11/2013
Citation: Harrison, R.L., Keena, M., Rowley, D.L. 2013. Genetic variation and biological activity of isolates of lymantria dispar multiple nucleopolyhedrovirus from North America, Europe, and Asia. In: 46th Annual Meeting of the Society for Invertebrate Pathology, August 11-15, 2013, Pittsburg, Pennsylvania. p.102. Interpretive Summary:
Technical Abstract: Little is known about genetic variation of Lymantria dispar multiple nucleopolyhedrovirus (LdMNPV; Baculoviridae: Alphabaculovirus) at the nucleotide sequence level. To obtain a more comprehensive view of genetic diversity among isolates of LdMNPV, partial sequences of the lef-8 gene were generated by PCR of 18 L. dispar virus samples isolated from the geographic range of the gypsy moth. Phylogenetic inference revealed a group of Asian LdMNPV isolates that formed a clade separate from LdMNPV isolates from Europe and North America. The complete genome sequence was determined for an isolate from this group, LdMNPV-2161 (Korea). The LdMNPV-2161 genome was 163,138 bp in length, 2,092 bp larger than the genome of LdMNPV isolate Cl5-6 (CT, USA). The two genomes shared an overall nucleotide sequence identity of 97.5% with 566 gaps inserted for alignment optimization. The difference in genome size was due primarily to additional members of the baculovirus repeated orf (bro) gene family in LdMNPV-2161 and the presence of a previously reported deletion of the p24 ORF and an adjacent ORF in LdMNPV Cl5-6. In bioassays against the New Jersey Standard Strain of L. dispar, isolates LdMNPV-3029 (Russia) and LdMNPV-Ab-a624 (MA, USA) killed neonate larvae with an LC50 approximately 2.5-fold lower than a sample of Gypchek® and isolates LdMNPV-3041 (Japan) and LdMNPV-2161 (Korea). This study expands our knowledge about about genetic variation among LdMNPV isolates and provides novel information on the distinct groups in which these NPVs occur.