Molecular characterization of Peanut Bud Necrosis Virus infecting tomato in Tamil Nadu

Abstract

Tomato bud blight caused by Peanut bud necrosis virus (PBNV) is an economically important disease affecting tomato causing great yield loss to the farming community. In the present study, the PBNV virus isolate, (GBNV CBE T02) was purified from the infected plant through mechanical transmission on cowpea cv. CO7, which produced chlorotic and necrotic local lesions on 4th days post inoculation. The pathogenicity of the virus on tomato cv. PKM1 was also proven via sap transmission. Transmission electron microscopy of infected tomato samples revealed spherical virus particle with diameter of 58 to 82 nm at 80000 X magnification. Amplification of the various genomic components of PBNV in the infected leaf samples through RT-PCR using gene specific primers produced an amplicon of 800 bp, 903 bp, 613 bp, 831 bp and 790 bp for RdRp, NSm, Gn/Gc, NP and NSs respectively. Sequence analysis of movement protein (NSm) (Gen Bank Acc. No. ON 529555) and Non-structural small protein (NSs) (Gen Bank Acc. No. ON529556) revealed that the isolate shared 98.98 % and 98.04 % identity respectively with other isolates in the GenBank database.