*Department of Plant Protection, Agricultural College and Research Institute, Tamil Nadu Agricultural University, Killikulam, Vallanad P.O.-628 252
**Department of Plant Pathology, Tamil Nadu Agricultural University, Coimbatore – 641 003
Online published on 25 November, 2011.
Sunflower (Helianthus annuus L.) cultivation has been hampered by a new viral disease in Tamil Nadu, India. Mechanical sap inoculation studies revealed that sunflower necrosis virus had a wide host range. The coat protein size of the purified virus was determined as 29 kDa in SDS-PAGE. Purified preparation of virus under transmission electron microscope revealed the presence of isometric particles. In DAC-ELISA test, infected sample showing different type of symptoms of sunflower necrosis virus (SFNV) were found to be positive when reacting with the homologous antiserum but not with the heterologous antiserum raised against GBNV. Using primers specific to the CP gene of Tobacco streak virus (TSV), RTPCR was successful in amplifying TSV CP gene (700bp) from ELISA positive samples. The coat protein gene of sunflower ilarvirus was 717 nucleotides long and the CP gene could potentially encode a protein of 237 amino acids. Multiple alignment of nucleotide sequence of coat protein gene of sunflower necrosis virus shared more than 90 per cent sequence homology with Tobacco streak virus. The nucleotide sequence data reported in this paper have been submitted to the Genbank nucleotide sequence database and has been assigned the accession number DQ 233634.
Helianthus annuus, sunflower necrosis virus (SFNV), host range, cloning, sequencing, Tobacco streak Ilarvirus,
