• The Plant Pathology Journal
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• v.18 no.5
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• pp.251-258
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• 2002

A potyvirus was isolated from cultivated Iris plants showing leaf streak mosaic symptom. Reverse transcription and polymerase chain reaction (RT-PCR) product of 1 kb long which encoded partial nuclear inclusion B and N-terminal region of viral coat protein (CP) genes for potyviruses was successfully amplified with a set of potyvirus-specific degenerate primers with viral RNA samples from the infected leaves: The RT-PCR product was cloned into the plasmid vector and its nucleotide sequences were determined. The nucleotide sequence of a CDNA clone revealed that the virus was an isolate of Ornithogalum moseic virus (OrMV) based on BLAST search analysis and was denoted as OrMV Korean isolate (OrMV-Ky). To further characterize the CP gene of the virus, a pair of OrMV-specific primers was designed and used for amplification of the entire CP gene of OrMV-Kr, The virus was easily and reliably detected from virus-infected Iris leaves by using the RT-PCR with the set of virus-specific primers. The RT-PCR product of the CP gene of the virus was cloned and its sequences were determined from selected recombinant CDNA clones. Sequence analysis revealed that the CP of OrMV-Kr consisted of 762 nucleotides, which encoded 253 amino acid residues. The CP of OrMV-Ky has 94.1-98.0% amino acid sequence identities (20 amino acid alterations) with that of other three isolates of OrMV, Two NT rich potential N-glycosylation motif sequences, NCTS and NWTM, and a DAC triple box responsible for aphid transmission were conserved in CPs of all the strains of OrMV. The virus has 58.5-86.2% amino acid sequence identities with that of other 16 potyviruses, indicating OrMV to be a distinct species of the genus. OrMV-Ky was the most related with Pterostylia virus Yin the phylogenetic tree analysis of CP at the amino acid level. This is the first report on the occurrence of OrMV in Iris plants in Korea. Data in this study indicate that OrMV is found in cultivated Iris plants, and may have mixed infection of OrMV and Iris severe mosaic virus in Korea.