Characterization and Partial Nucleotide Sequence of Potato Virus X Isolated from Potato in Korea

  • Jung, Hyo-Won (School of Agricultural Biotechnology, Seoul National University) ;
  • Yun, Wan-Soo (School of Agricultural Biotechnology, Seoul National University) ;
  • Seo, Hyo-Won (Alpine Agricultural Experiment Station, Pyungchang) ;
  • Hahm, Young-Il (Alpine Agricultural Experiment Station, Pyungchang) ;
  • Kim, Kook-Hyung (School of Agricultural Biotechnology, Seoul National University)
  • Published : 2000.04.01

Abstract

Potato virus X (PVX-KO) showing mild mosaic and stunting symptoms on potato (Solanum tuberosum) in Kangwon area has been isolated and characterized. EM observation of the purified virus particles showed flexuous rod shape of about 520 nm in length. The coat protein (CP) of the virus had a molecular weight of 31 kDa in SDS-PAGE analysis, and the viral RNA was approximately 6.4 kb in size in denatured agarose gel electro-phoresis. In gel-immunodiffusion tests, it reacted strongly with an antiserum to common PVX from BIOREABAAG (USA). A rabbit antiserum was produced using purified virus and used for routine PVX detection by ELISA. Cultivated potatoes in Kangwon and other areas were frequently infected with PVX-KO. Both Datura stramonium and Nicotiana tabaccum cultivars developed necrotic local lesions 5 days after inoculation, and systemic mosaic symptoms with vein clearing 2 weeks after inoculation. All the features agree with the description of other PVX strains. To confirm and determine PVX strains, reverse transcription-polymerase chain reaction experiment was conducted using specific primers for viral CP. Amplified DNA fragments were cloned and sequenced. Results showed nucleotide sequence homologies of about 88 to 99% to other PVX strains. Based on CP amino acid sequence deduced from nucleotide sequences and host range studies PVX-KO is considered a member of the type X subgroup of PVX.

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