ISOLATION, REPLICATION AND POLYHEDRIN GENE SEQUENCE OF AN ISRAELI HELICOVERPA-ARMIGERA SINGLE NUCLEOPOLYHEDROVIRUS

A local strain of Helicoverpa armigera baculovirus was isolated from i nfected H. armigera larvae. Infectivity to Helicoverpa cells, restrict ion enzyme analysis and electron microscopy allowed its identification as a single embedded nucleopolyhedrovirus, designated HaSNPV-IS. Anal ysis of DNA replication, protein synthesis and polyhedrin expression i n HaSNPV-infected cells located the late and very late phases of the v iral cycle at 24 and 48 h after infection, respectively. The viral pol yhedrin gene was isolated and characterized. It encoded for a polypept ide of 246 amino acid residues. A 32 kDa polypeptide was identified by immunoblot analysis using anti-polyhedrin antiserum. The HaSNPV-IS po lyhedrin DNA sequence revealed 99.4% of homology to the HzSNPV polyhed rin. The availability of this efficient replication system and the abo ve knowledge paves the way to future genetic engineering of the HaSNPV .