Two new bipartite begomoviruses infecting Wissadula amplissima in Jamaica

Abstract

Begomoviruses are whitefly transmitted, single-stranded DNA viruses that infect dicotyledons (Stanley et al. , 2005). In Jamaica, the weed Wissadula amplissima is a host of the begomovirus Wissadula golden mosaic virus (WGMV)(Roye et al. , 1997). Total DNA was extracted from two W. amplissima plants (W96 and W132) showing symptoms, collected in November 2004 and February 2005 respectively. DNA-A and DNA-B amplicons of 1·4 kb were generated from these samples in PCR using primer pairs PAC1v1978/PAV1c715 and PBC1v2039/PBV1c800 for DNA-A and DNA-B respectively. These fragments were cloned and sequenced (Rojas et al. , 1993). Analysis of the intergenic region (IR) sequence, revealed that the DNAA and DNA-B clones from sample 96 (W96AT and W96BT respectively) are cognate components of a bipartite begomovirus with 94% sequence identity. Clone pW96AT (1385 nt; DQ395342) encompasses the IR and the 5 ′ ends of the replication-associated and coat protein genes, and showed the highest nucleotide sequence identity (81%) to Tomato mild yellow leaf curl Aragua virus (AY927277). Clone pW96BT, consisting of 845 nt encompassing the 5 ′ part of the nuclear shuttle protein ( NSP ) gene and IR, showed the highest identity (50%) to Macroptilium golden mosaic virus -[Jamaica: 2] (AF098939). A DNA-A sequence identity of less than 89% to reported geminiviruses suggests that this geminivirus is previously unreported and has been tentatively named Wissadula golden mosaic St. Elizabeth virus (WGMSEV). The IRs of the DNA-A and DNA-B clones from sample 132 (W132AT and W132BT) show 89% identity, suggesting that they could form an infectious unit. Clone W132AT (1384 nt, DQ395343) is most closely related (77%) to WGMV-[Jamaica:1] and Jatropha mosaic virus (JMV; AF324410), whilst W132BT (DQ395344) shows 62% identity to JMV (AF324411) over 1488 nt, encompassing the 5 ′ part of the NSP and movement protein genes and the IR. This virus was provisionally named Wissadula golden mosaic St. Thomas virus (WGMSTV). The DNA-A and DNA-B components of WGMSTV and WGMSEV show 55% and 37% identity, respectively. This is the first report of WGMSEV and WGMSTV.