Baculovirus-mediated expression of a Chinese scorpion neurotoxin improves insecticidal efficacy

An Buthus martensii Karsch Insect Toxin (BmK IT) gene was inserted into the genome of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) to construct a recombinant baculovirus, AcMNPV-BmK IT. The expression of BmK IT was confirmed using RT-PCR, dot blot and SDS-PAGE analysis. Dose-lethal time responses to Spodoptera exigua larvae were compared between wild-type baculovirus AcMNPV and recombinant virus AcMNPV-BmK IT. At the concentration of 1 × 10⁷ PlBs/mL, the median lethal time of recombinant baculovirus (LT₅₀ = 73.6 h) on third instar S. exigua larvae showed an improvement of 13.2% over the efficacy of wild type virus (LT₅₀ = 84.8 h) during a 192 h infection. Supported by the National Natural Science Foundation of China (Grant Nos. 30670282 and 30700534) and the Department of Science and Technology of Shanxi Province