Identification and characterization of Tobacco streak virus, as a new causative agent of necrosis disease of Anthurium

Abstract

Tobacco streak virus (TSV) was detected from Anthurium samples collected from Anthurium variety Medioria Red from College of Horticulture, Bangalore, India grown under polyhouse cultivation. Sap inoculation of the samples expressing positive reaction through direct antigen coating-enzyme linked immunosorbant assay (DAC-ELISA) produced both localized and systemic infection. The localized infection produced circular necrotic lesions on the leaves of cowpea cv. C152 plants. The samples were also confirmed through dot blot immunibinding assay (DIBA), which showed positive reaction by producing circular, purple coloured spot against TSV specific antibody. Further molecular characterization of TSV through RT-PCR with coat protein gene specific primers produced amplicon size of 929 bp pertaining to RNA3 region. The basic local alignment search tool (BLAST) analysis of coat protein gene through National Centre for Biotechnology Information (NCBI) database had nucleotide and amino acid sequence similarity of 97.6 to 98.8 % and 94.9 to 97.4 %, respectively with known strains of TSV from India. Phylogenetic analysis of the nucleotide sequences Confirmed the Anthurium strain of TSV forms single subgroup with other crop of Indian isolates. This study provides important clues about spread of TSV. To the best of our knowledge it is the first detailed study of TSV infecting Anthurium.