Comparative study of hot-start PCR characterized species specific conserved gene regions of a biocontrol agent Helicoverpa armigera nucleopolyhedrovirus with its whole genome

Abstract

The present investigation was aimed to isolate the strain of Helicoverpa armigera nucleopolyhedrovirus (HearNPV) from virus infected larvae collected from Ludhiana, India during October 2015. Four conserved gene regions of Helicoverpa armigera NPV (HearNPV) genome, viz, polyhedrin (polh), inhibitor of apoptosis-2 (iap2), DNA binding protein (dbp) and per os infectivity factor-1 (pif1) genes were characterized by species-specific primers, based on a Hot-Start PCR approach, for an Indian strain of HearNPV. The species-specific primers designed for these genes enabled a successful amplification with the expected base pair size. In search of any insertion / deletion/ difference in the nucleotide sequences, a comparative analysis was studied between these PCR characterized genes and the respective ORFs from the recently sequenced genomes of HearNPV L1 (India), HearNPV SP1A (Spain), HearNPV NNg1 (Kenya) and HearNPV G4 (China). Newly designed species specific primers will also help in quick and reliable identification of HearNPV in the baculovirus sample.