Antiviral Treatment Reveals a Cooperative Pathogenicity of Baculovirus and Iflavirus in Spodoptera exigua, a lepidopteran insect.

Antiviral Treatment Reveals a Cooperative Pathogenicity of Baculovirus and Iflavirus in Spodoptera exigua, a lepidopteran insect. J Microbiol Biotechnol. 2021 Jan 22;: Authors: Roy MC, Ahmed S, Mollah MMI, Kim Y Abstract The beet armyworm, Spodoptera exigua, is a serious insect pest infesting various vegetable crops. Two infectious insect viruses, baculovirus and iflavirus, are known to induce epizootic in S. exigua populations. Indeed, some laboratory colonies appeared to be covertly infected by these viruses. Diagnostic PCR tests detected two kinds of viruses: Spodoptera exigua multiple nucleopolyhedrosis virus (SeMNPV) and iflaviruses (SeIfV1 and SeIfV2). Viral extract from dead larvae of S. exigua could infect Sf9 cells and produce occlusion bodies (OBs). Feeding OBs to asymptomatic larvae of S. exigua caused significant viral disease. Interestingly, both SeIfV1 and SeIfV2 increased their titers at late larval stages. Sterilization of laid eggs with 1% sodium hypochloride significantly reduced SeMNPV titers and increased larval survival rate. Double-stranded RNA (dsRNA) specific to SeIfV1 or SeIfV2 significantly reduced viral titers and increased larval survival rate. To continuously feed dsRNA, a recombinant Escherichia coli HT115 expressing SeIfV1-dsRNA was constructed with an L4440 expression vector. Adding this recombinant E. coli to the artificial diet significantly reduced the SeIfV1 titer and increased larval survival. The...
Source: Journal of Microbiology and Biotechnology - Category: Biotechnology Authors: Tags: J Microbiol Biotechnol Source Type: research