الفهرس | Only 14 pages are availabe for public view |
Abstract A strain of Heliothis armigera nucleopolyhedrovirus (HaNPV) was isolated from infected H. armigera larvae because of its potential for use as an insect pest control agent. A procedure to assess pathogenicity (LC50) is crucial for research into the use of pathogen as biocontrol agents. Morphological effects and Histological changes were observed by using (SEM) and light microscope respectively showing the destructive of larvae body, the midgut and all it’s component cells as (columnar, globet and regenerative). The partial nucleotide sequence of the PCR–amplified fragment (497pb) for the polyhedrin gene of HaNPV- EG isolate encoded a protein of 165amino acid with molecular weight (19.3005 KDa). The nucleotides and amino acids were compared with the sequence of another nine NPV isolates registered in Gen Bank and recorded complete similarity 100% in nucleotide sequence between HaNPV- EG and HaNPV India and HaNPV Japan and slight difference in nitrogen base situation with the other compared NPV isolates did not exceed 0.1%. Production of polyclonal antibodies was produced by immunizing rabbit with highly purified polyhedra of HaNPV antigen. The produced antiserum have a highly titre as 1/1024. Serological technique as precipitation test, the enzyme linked immunosorbent assay (ELISA) and ouchterlony double diffusion test has been shown to be a specific and sensitive method to detect a nuclear polyhedrosis virus of HaNPV. Key words: Heliothis armigera, insect virus, economic insect, histopathology, SEM, light microscope, serology, PCR. |