title: Genetic Diversity and Pathogenicity of Cylindrocarpon destructans Isolates Obtained from Korean Panax ginseng.
abstract: We analyzed the genetic diversity of Cylindrocarpon destructans isolates obtained from Korean ginseng (i.e., Panax ginseng) roots by performing virulence tests and nuclear ribosomal gene internal transcribed spacer (ITS) and mitochondrial small subunit (mt SSU) rDNA sequence analysis. The phylogenetic relationship analysis performed using ITS DNA sequences and isolates from other hosts helped confirm that all the Korean C. destructans isolates belonged to Nectria/Neonectria radicicola complex. The results of in vivo and ex vivo virulence tests showed that the C. destructans isolates could be divided into two groups according to their distinctive difference in virulence and the genetic diversity. The highly virulent Korean isolates in pathogenicity group II (PG II), together with foreign isolates from P. ginseng and P. quinquefolius, formed a single group. The weakly virulent isolates in pathogenicity group I, together with the foreign isolates from other host plants, formed another group and exhibited a greater genetic diversity than the isolates of PG II, as confirmed by the mt SSU rDNA sequence analysis. In addition, as the weakly virulent Korean isolates were genetically very similar to the foreign isolates from other hosts, they were likely to originate from hosts other than the ginseng plants.
authors: Department of Applied Biology, Chungnam National University, Daejeon 305-764, Korea.
authors: Jeong Young
authors: JY
authors: Song
authors: Department of Applied Biology, Chungnam National University, Daejeon 305-764, Korea.
authors: Mun Won
authors: MW
authors: Seo
authors: Keumsan Ginseng & Medicinal Crop Experiment Station, Chungcheongnam-do Agricultural Research & Extension Services, Geumsan 312-823, Korea.
authors: Sun Ick
authors: SI
authors: Kim
authors: Nonsan Strawberry Experiment Station, Chungcheongnam-do Agricultural Research & Extension Services, Nonsan 320-862, Korea.
authors: Myeong Hyeon
authors: MH
authors: Nam
authors: Department of Applied Biology, Chungnam National University, Daejeon 305-764, Korea.
authors: Hyoun Sub
authors: HS
authors: Lim
authors: Department of Applied Biology, Chungnam National University, Daejeon 305-764, Korea.
authors: Hong Gi
authors: HG
authors: Kim
keywords: Cylindrocarpon destructans; Genetic diversity; Ginseng root rot; Panax ginseng; Pathogenicity