Abstract

Begomovirus isolates, exhibiting identity of 89 and 93% with Radish leaf curl virus(RaLCV), were detected from the leaf curl disease affected okra (Abelmoschus esculentus) plants in Bihar, India. The detected isolates are supposed to be a new strain of RaLCV and therefore are referred to here as RaLCV-Hajipur1 and RaLCV-Hajipur2. Alphasatellite was identified as Cotton leaf curl Burewala alphasatellite (CLCuBuA) and betasatellite as Tomato leaf curl Bangladesh betasatellite (ToLCBDB). The aforementioned RaLCV-Hajipur isolates were used to construct infectious clones. These isolates were inoculated separately or together with alpha- and betasatellites in tobacco. The begomovirus and satellites were isolated from tobacco plants at twenty seven day post inoculation and then sequenced. Analysis of the sequences revealed the presence of a new isolate, referred to here as RaLCV-Hajipur3. Recombination analysis using recombination detection program 3 (RDP3) revealed that the RaLCV-Hajipur1, RaLCV-Hajipur2 and RaLCV-Hajipur3 had recombinant origin. RDP3 analysis of the RaLCV-Hajipur3 revealed that the two inoculated isolates (RaLCV-Hajipur1 and RaLCV-Hajipur2) were the probable major and minor parents of the newly detected isolate (RaLCV-Hajipur3).

Key words: Begomovirus, betasatellite, alphasatellite, recombination, evolution.