Molecular characterization of a begomovirus associated with yellow mosaic disease of Acalypha indica
摘要
Begomovirus, a genus within the family Geminiviridae, is the largest genus of plant-infecting viruses. Several recent studies have reported the prevalence of begomoviruses in common weeds. In the present study, Acalypha indica, a euphorbiaceous weed exhibiting yellow mosaic symptoms, was screened for begomovirus infection. The analyzed samples revealed the presence of a bipartite begomovirus with a complete sequence of DNA-A and B components, each of approximately 2.7 kb in size, showing genome organization typical of Old World bipartite begomoviruses. While the DNA-A (GenBank accession number PQ067511) component showed 93% similarity with Jatropha leaf yellow mosaic Katarniaghat virus (JLYMKV-A, JN135236.1), the DNA-B (PQ067512) component closely resembled Rose leaf curl virus (RoLCV-B, OQ440773.1) with approximately 83% similarity. Notably, previous studies have not reported an association of DNA-B components with JLYMKV-A. The sequence analysis revealed that the DNA-B genome has a single recombination event between Sri Lankan cassava mosaic virus DNA-B (SLCMV-B) and RoLCV DNA-B. Further, the common region (CR) analysis revealed a high nucleotide identity of 97% between the DNA-A and B components isolated in this study, suggesting that these are cognate molecules. In summary, the current study, for the first time, reports a novel recombinant DNA-B component with JLYMKV-A causing yellow mosaic disease in A. indica in India.