重組加州苜蓿夜蛾核多角體病毒擴增寄主範圍提高對斜紋夜蛾幼蟲之致病力

This study was based on the Spodoptera
litura nucleopolyhedrovirus (SpltNPV) to
clone the gene which could increase
pathogenicity to the larva of S. litura.
Furthermore, the gene related to the host
range was incorporated to Autographa
californica nucleopolyhedrovirus (AcMNPV)
by means of genetic engineering to generate
recombinant virus. The recombinant virus
was used to feed S. litura larvae for
determining its the pathogenicity. First of all,
the genomic library of SpltNPV was
established by digesting DNA of SpltNPV
with several restriction enzymes such as
EcoRI. DNA fragments from established
genomic library were cloned to the transfer
vector pFastBacHTa of AcMNPV. Thirteen
clones of recombinant transfer vector
contained different EcoRI fragments of
SpltNPV were obtained. These transfer
vectors were used to generate recombinant
AcMNPV by using Bac-to-Bac expression
vector system. There were eight different
recombinant viruses obtained. The preoccluded
form virus was used to bioassay 1st
instar of S. litura. Results revealed that
pathogenicity of 8 recombinant viruses were
less than 30%, and there were no significant
difference between recombinant viruses and
wild type AcMNPV. This indicated that all
recombinant viruses did not contain host
range related gene of SpltNPV.