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Page number:847 
Remarks (public):Five-septate conidia formed by F. ussurianum on SNA under black light are slightly wider than 5 µm on average. The measurements are similar to F. vorosii and F. aethiopicum, both of which are members of the Fg species complex (Figs. 4-5, O'Donnell et al 2008). However F. vorosii and F. aethiopicum produce mostly straight conidia, which are asymmetrical in that they are typically widest above the mid-region. By comparison conidia produced by F. ussurianum are typically curved and nearly symmetrical (Figs. 3-5). Fusarium ussurianum is most similar morphologically to F. cerealis (Cooke) Sacc. (= F. crookewellense Burgess et al) because both form nearly symmetrical conidia tapering and curving equally toward both ends (Burgess et al 1982, Nirenberg 1990). Fusarium cerealis however produces conidia that are widest at the mid-region and forms chlamydospores abundantly (Burgess et al 1982, Aoki and O'Donnell 1999, O'Donnell et al 2004). In strains of F. ussurianum by way of contrast conidia are widest slightly above the mid-region and chlamydospores were never observed. Delimitation of F. ussurianum is strongly supported with the exclusivity criterion under GCPSR in that it received strong MP and MP monophyly bootstrap support from analyses of -tubulin, ?-tubulin, EF-1a, HIS, MAT, reductase, URA-Tri101-PHO and the combined partition (Table I). Fusarium ussurianum and F. asiaticum are strongly supported as sisters in the multilocus phylogeny (Fig. 2) and together with F. vorosii appear to represent an Asian clade within the Fg species complex.  
Description type:Original description 
Description:Fusarium ussurianum T. Aoki, Gagkaeva, Yli-Mattila, Kistler, O'Donnell, sp. nov.
MycoBank MB 512612 Figs. 1-5
Colonies in darkness at 20 C on PDA show average growth of 2.8-10.1 mm per d. Colony color on PDA red, pastel-red, brownish-red, grayish-red, reddish-white, grayish-brown, brownish-yellow to white; reverse pigmentation red, deep-red, reddish-brown, brownish-red, brownish-violet, ruby, reddish-white to white. Colony margin entire to undulate. Odor absent or moldy. Aerial mycelium on PDA generally abundant, some sparsely developed, loose to densely floccose, white, reddish-white, brownish-yellow, brownish-orange to grayish-brown. Hyphae on SNA 1.5-7 µm wide. Chlamydospores and sclerotia absent but some globose hyphal swelling sometimes present, intercalary or occasionally terminal. Sporulation on SNA under black light quick and abundant, starting within a few days from conidiophores formed directly on hyphae or aggregated in sporodochia on the agar surface; in darkness sporulation retarded and sparse; sporodochia sparse or abundant. Conidiophores branched verticillately or unbranched, forming monophialides on the apices or abbreviated as single monophialides formed on running hyphae. Phialides simple, subulate, ampulliform to subcylindrical, sometimes doliiform, monophialidic. Conidia of a single type, typically falcate and curved, dorsiventral, most frequently widest slightly above the mid-region of their length, mostly tapering and curving equally toward both ends, with an arcuate apical cell and a distinct basal foot cell, forming symmetrical upper and lower halves, (1-)3-5(-7)-septate. In some strains conidia were observed that were almost cylindrical and gently curved. Under black light, 5-septate conidia: 30-75.5 x 4-6 µm in total range, 39.3-59.8 x 5.0-5.2 µm on average, (ex-type strain: 45.5-59.8-75.5 x 4-5.1-6 µm).
Holotypus: BPI 878845, a dried culture, isolated from an oat seed, Avena sativa L. in a field near Ussuriysk, Primorsky krai, Russian Federation, in 2002, deposited in herbarium BPI (US National Fungus Collection, Beltsville, Maryland). Ex holotype culture: NRRL 45681 = TG-2662/0 = CBS 123752.
Other strains examined. - NRRL 45665 = TG-2981/3 = CBS 123751 ex wheat seed in JAR, Russian Federation, in 2002; NRRL 45795 = TG-65202 = CBS 123753 ex wheat seed in Kamen-Ribolov, Russian Federation, in 2006; and NRRL 45833 = TG-k.3-6 = CBS 123754 ex rot of wheat (root rot) in an agricultural field near Ussuriysk, Russian Federation, in 2006.
Distribution. - Kamen-Ribolov and near Ussuriysk in Primorsky krai, and the Jewish Autonomous Region in the Far East of the Russian Federation.
 
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