两个EoNPV毒株对茶尺蠖和灰茶尺蠖的毒力差异

通过确定不同茶尺蠖核型多角体病毒(Ectropis obliqua nucleopolyhedrovirus,EoNPV)毒株对茶尺蠖(Ectropis obliqua)和灰茶尺蠖(Ectropis grisescens)毒力水平的差异,为有效提高茶尺蠖病毒的防效提供理论基础.采用浸渍法,测定EoNPV浙江毒株(EoN...

Virulence Difference of Two Strains of EoNPV Isolates to Ectropis obliqua and Ectropis grisescens

The virulence differences of Ectropis obliqua nucleopolyhedrovirus (EoNPV) from different isolates to Ectropis obliqua and Ectropis grisescens were analyzed, which provided a basis for effectively improving the control effect of EoNPV. The virulence of EoNPV Zhejiang strain (EoNPV-ZJ) and EoNPV Jiangxi strain (EoNPV-JX) to third instar larvae of E. obliqua and E. grisescens were determined by leaf dipping. The homologous regions (hrs) of EoNPV-ZJ and EoNPV-JX were further sequenced and analyzed by multiple sequence alignment. The results indicate that the 14 d LC₅₀ of EoNPV-JX to E. grisescens and E. obliqua were 5.95×10⁶ PIB·mL^-1 and 3.14×10⁶ PIB·mL^-1, respectively, while the 14 d LC₅₀ of EoNPV-ZJ to the two tea geometrid moths were 1.13×10⁷ PIB·mL^-1 and 5.04×10⁶ PIB·mL^-1, respectively. The hr1 of EoNPV-JX and EoNPV-ZJ were both 1 795 bp in size, containing 11 complete palindrome sequences, and hr3 were both 665 bp in size, containing 3 complete palindrome sequences, which were the same as EoNPV Anhui strain (EoNPV-AH). However, the hr2 regions of the three strains were different. The hr2 of EoNPV-JX was 864 bp in size and contained 7 complete palindrome sequences, and it was 1 168 bp in size and contained 12 complete palindrome sequences in EoNPV-ZJ, all of which were less than the 18 complete palindrome sequences of hr2 in EoNPV-AH. Our study suggests that the virulence of different strains of EoNPV to E. obliqua were higher than that of its related species, E. grisescens, while the toxicity of EoNPV-JX to E. grisescens was more than that of EoNPV-ZJ. The sensitivity of E. obliqua to EoNPV was higher than that of E. grisescens. The virulence of EoNPV might be related to the number of palindromes of hr2.