The Differences Of Effect Of EoNPV On The Sibling Species Of Ectropis Obliqua And Ectropis Grisescens

Ectropis obliqua Prout and Ectropis grisescens Warren are leaf-eating sibling species which seriously damaged the tea garden.It is difficult to distinguish between E.obliqua and E.grisescens Because of the similar morphological characteristics and biological habits,they always been regarded as one kind of tea geometrid for field control the control effects of highly specific EoNPV?E.obliqua nucleopolyhedrovirus?on tea geometrid are significantly different in different areas,then studies shown that there are two sibling species.In this paper,E.obliqua and E.grisescens larvae were infected by three different concentrations of EoNPV respectively and the mortality rates of two species were contrasted and analyzed,in order to further verify the control effect of Eo NPV on E.obliqua and E.grisescens in the fields.With feed on EoNPV at a concentration of 1×10⁷ PIB/mL,the difference of virus particles proliferation dynamics in the two sibling Ectropis species was measured by qPCR?Quantitative real-time PCR?,so as to explain the reason on mortality rate differences in the two species infected by EoNPV.Besides,based on the transcriptome data of EoNPV infected E.grisescens,the immune related antibacterial peptide genes were screened and gene expression differences were detected by qPCR in the sibling species to further explain the mechanism of mortality rate difference caused by EoNPV from the perspective of antimicrobial peptide gene expression.Three conclusions of this study were shown as followed:1.Infected by three different concentrations of EoNPV on the sibling species,the results of toxicity test showed that the cumulative mortality rates of E.obliqua were significantly different with different concentrations of EoNPV?P<0.05?,while there were no significant differences in the cumulative mortality rates of E.grisescens.Comparing the lethal effect of same concentration of EoNPV on the sibling species,the cumulative mortality rate of E.obliqua was significantly higher than that of E.grisescens infected EoNPV,indicating that E.obliqua was highly sensitive to EoNPV and the sensitivity of E.grisescens to EoNPV was low.2.By detecting the proliferation of virus particles in two sibling species,the number of virus copies in E.obliqua began to proliferate rapidly at 18^th hour after infected by EoNPV,while the virus began to proliferate rapidly in E.grisescens at 36^th hour.The rapid reproduction time of EoNPV in E.obliqua was earlier than E.grisescens,and the absolute numbers of viruses in E.obliqua were significantly higher than E.grisescens at different time points respectively after infected by EoNPV,which indicated that E.obliqua was more suitable for EoNPV proliferation.This may also be the reason why the lethal rate of E.obliqua is significantly higher than E.grisescens after infecting EoNPV.3.As further determined by qRT-PCR,the transcript levels of gloverin,attacin and moricin genes were up-regulated in the two sibling Ectropis species after infected by EoNPV.The highest expression level of gloverin was detected at 12^th h-group,while moricin was expressed highest at 48^th h-group.The transcript levels of gloverin and moricin were significantly higher in E.grisescens with respect to E.obliqua.However,attacin without the similar pattern indicated that gloverin and moricin were potentially associated with active resistance to virus infection.The results will lay the foundation for further revealing an underlying role of antimicrobial peptide genes in the interaction between insects and viruses.