Potential use of a group II alphabaculovirus isolated from Mamestra brassicae as a broad-spectrum biological pesticide

ABSTRACTA novel native isolate of Mamestra brassicae nucleopolyhedrovirus, designated MabrNPV-CHb1, was identified in this study. The complete nucleotide sequence of MabrNPV-CHb1 was determined. The MabrNPV-CHb1 genome consists of 154,451 bp, with a G + C content of 40.05%. The genomic sequence and comparative analysis indicated that MabrNPV-CHb1 shares high nucleotide identity with MabrNPV-K1, HearMNPV, MacoNPV-B and MacoNPV-A. The major difference between MabrNPV-CHb1 and MabrNPV-K1 is the absence of MabrNPV-CHb1 ORF134 in MabrNPV-K1. The MabrNPV-CHb1 ORF134 is a gene encoding a putative transposase, and phylogenetic analysis suggests that it is derived through horizontal gene transfer (HGT) from ascoviruses. MabrNPV-CHb1 exhibits broad-spectrum activity against lepidopteran agricultural pests, including insects in the families Noctuidae and Plutellidae. A high yield of MabrNPV-CHb1 occlusion bodies was obtained by propagation in alternative hosts, demonstrating its potential for pesticide application. ...