Identification of Chinese Yam Necrotic Mosaic Virus(ChYNMV) infecting Chinese yam(Dioscorea opposita Thunb. cv. Jang-Ma) in Korea.

Chinese yam(D. opposita Thunb. cv. Jang-Ma) plants showing necrotic mosaic symptom were collected from their growing fields in Andong, Korea. Electron microscoptic examination of negatively stained preparations showed filamentous particles of 660nm in length. The virues purified partially were used to isolate Viral RNA as template for RT-PCR to amplify the CP gene with ChYNMV specific and oligo dT primers. Amino acids sequeces revealed that the viruses shared 99.3％ similarity with ChYNMV(AB044386) which was known as the member of macluravirus. So the viruses from Chinese yam(D. opposita Thunb. cv. Jang-Ma) plants were identified as ChYNMV. Comparing the amino aced sequences of ChYNMV strains with other macluraviruses such as CdMV, NLV and MacMV revealed that N-terminal was the most variable region and conserved regions were present within the genus Macluravirus.