Sensitivity of Polyvoltine Thai Strains of Bombyx mori to a BmNPV Isolate From Mahasarakham

Abstract

Virus infection by the Bombyx mori nucleopolyhedrovirus (BmNPV) is the most severe disease in Thai sericultural practice of polyvoltine silkworms. Here, we characterized a newly isolated BmNPV isolated from the Mahasarakham province in Thailand (BmNPV-MSU). The purity and morphology of BmNPV-MSU were examined using light microscopy and scanning electron microscopy. The polyhedral inclusion bodies (PIBs) of BmNPV-MSU appeared in tetragonal, hexagonal, octagonal, and globular forms. The virions were both single and multiple embedded as observed by transmission electron microscopy. We also determined the virulence of BmNPV-MSU for six different Thai polyvoltine strains by LC50 and time to death after infection. The LC50 values of Nang Lai, NK04, and Sam Rong strains were 5.05-1.52 x 10(7) PIBs per ml and mortality peaked 7- to 8-d after inoculation. For Nang Noi, SP2, and RE05 strains the LC50 values were 7.91-1.82 x 10(6) PIBs/ml and mortality peaked 4-5 d after inoculation, thus having lower chance of survival to infection by BmNPV-MSU.

Keywords

polyvoltine; Bombyx mori; nucleopolyhedrovirus; BmNPV-MSU; virulence

Published in

Journal Of Insect Science (Online)
2020, volume: 20, number: 2, article number: ieaa023
Publisher: OXFORD UNIV PRESS INC

SLU Authors

• Terenius, Olle

  • Department of Ecology, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Microbiology

Publication identifier

• DOI: https://doi.org/10.1093/jisesa/ieaa023

Permanent link to this page (URI)

https://res.slu.se/id/publ/105589