title: Characterization of Chinese  eggplant isolates of the fungal pathogen Verticillium dahliae from  different geographic origins.
abstract: Verticillium  dahliae is a fungal pathogen that causes wilt disease in a  wide range of host plants. Characterization of virulence, morphological, and  molecular variations among V. dahliae isolates from different geographic  origins is essential for any breeding program aimed at producing plant  cultivars resistant to this disease. We characterized virulence variation among V. dahliae isolates from Chinese cultivated eggplant grown in Northeast  China by pathogenicity testing on susceptible, moderately resistant, and  resistant eggplant accessions in a glasshouse using a root-dipping method of  infection. These isolates were also characterized for morphological features  based on growth on potato dextrose agar media and for genetic variation based  on ISSR markers. All 12 isolates were divided into three pathotypes based on  the virulence, i.e., strong, moderate, or weak type. Three isolates were categorized  as defoliating pathotypes, with strong virulence, and the rest of the isolates  were categorized as non-defoliating pathotypes, with moderate to weak  virulence. The eggplant isolates were classified into three morphological types  or morphotypes, hypha, hypha-sclerotia, and sclerotia; no significant  correlations were detected between pathotypes and morphotypes or geographic  origins. ISSR fingerprinting indicated genetic diversity among isolates,  ranging from 0.26 to 0.69. Specific fingerprint types were not correlated with  either pathotype or morphotype. However, ISSR analyses did reveal two clusters  in which the isolates in each share the same or neighboring geographic origins.
authors: Nanjing Agriculture University, Nanjing, China.
authors: Z
authors: Z
authors: Xu
authors: Z
authors: Z
authors: Ali
authors: X
authors: X
authors: Hou
authors: H
authors: H
authors: Li
authors: J X
authors: JX
authors: Yi
authors: P A
authors: PA
authors: Abbasi
mesh_terms: D002681:China; D016172:DNA Fingerprinting / Q000379:methods; D014644:Genetic Variation; D005843:Geography; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology*; D018517:Plant Roots / Q000382:microbiology; D032323:Solanum melongena / Q000382:microbiology*; D020172:Verticillium / Q000235:genetics*; D014774:Virulence / Q000235:genetics