This Article Full Text Full Text (PDF) All Versions of this Article: 08-217v1 101/6/841    most recent Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Permissions Google Scholar Articles by Yli-Mattila, T. Articles by O’Donnell, K. PubMed Articles by Yli-Mattila, T. Articles by O’Donnell, K. Agricola Articles by Yli-Mattila, T. Articles by O’Donnell, K.

A novel Asian clade within the Fusarium graminearum species complex includes a newly discovered cereal head blight pathogen from the Russian Far East

     Laboratory of Plant Physiology and Molecular Biology, Department of Biology, University of Turku, FIN-20014 Turku, Finland

Tatiana Gagkaeva

     Laboratory of Mycology and Phytopathology, All-Russian Institute of Plant Protection (VIZR), 196608 St Petersburg-Pushkin, Russia

Todd J. Ward

     Microbial Genomics Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, Illinois 61604

Takayuki Aoki

     NIAS Genebank-Microorganisms Section (MAFF), National Institute of Agrobiological Sciences (NIAS), 2-1-2 Kannondai, Tsukuba, Ibaraki 305-8602, Japan

H. Corby Kistler

     Cereal Disease Laboratory, U.S. Department of Agriculture, Agricultural Research Service, 1551 Lindig Street, St Paul, Minnesota 55108

Kerry O’Donnell ¹

     Microbial Genomics Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, Illinois 61604

We investigated Fusarium graminearum complex (Fg complex) species diversity and toxin potential in European and Asian regions of the Russian Federation and adjoining regions northwest to Finland and south near Harbin, Heilongjiang Province, China, to expand our knowledge of the host range and geographic distribution of these economically devastating cereal head blight pathogens. Results of a recently described multilocus genotyping (MLGT) assay revealed that F. graminearum was the sole Fg complex pathogen in northern Europe and the predominant one in Asia (90.5%). Even though isolates of F. graminearum were segregating for 3-acetyldeoxynivalenol (3ADON) and 15-acetyldeoxynivalenol (15ADON) chemotype in nearly equal frequencies in the regions sampled on both continents, significant differences in the geographic distribution of isolates producing these acetyl ester derivatives of deoxynivalenol (DON) were observed in Europe. While 93.5% of the isolates in southern Russia (n = 43 of 46) possessed the 15ADON chemotype, isolates of F. graminearum recovered in Finland and northwestern Russia (n = 40) were exclusively 3ADON producers. Based on results of the MLGT assay, species identity of 10 genetically novel Fg complex isolates from the Russian Far East was investigated further via molecular phylogenetic analyses of multi-locus DNA sequence data. Results of these analyses resolved these isolates as a phylogenetically distinct, reciprocally monophyletic sister lineage of F. asiaticum, which together with F. vorosii form a newly discovered Asian clade within the Fg complex. Because this novel lineage fulfills the highly conservative criterion of genealogical exclusivity under phylogenetic species recognition it is formally described herein as F. ussurianum. In addition to morphologically characterizing isolates of F. ussurianum, experiments were conducted to assess pathogenicity to wheat and trichothecene toxin potential in planta.

Key words: deoxynivalenol, genotyping, mycotoxin, nivalenol, phylogenetics, trichothecene