The silkworm Bombyx mori has been exploited as a silk producer
in the silk industry for thousands of years. It is an economically
important insect and a model insect for studies in entomology,
molecular biology and biotechnology [1]. B. mori nucleopolyhedrovirus
(BmNPV), the insect virus firstly discovered, causing nuclear
polyhedrosis disease in B. mori, which is the most serious of
three viral diseases (BmNPV, densonucleosis virus (DNV), cytoplasmic
polyhedrosis virus (CPV)) in sericulture. The disease often
breaks out in sericultural countries and due to its high infectivity; it
is difficult to control, resulting in heavy economic loss.