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Remarks (public):For a complete description including images see www.cababstractsplus.org/dfb 
Remarks (internal):Although many isolates produce macroconidia only sparsely, the fungus may still be recognised by its tendency to produce abundant chlamydospores in clumps and its distinctive colony morphology on PSA. This species was included in Fusarium sect. Discolor by Wollenweber & Reinking (1935). It is quite distinctive in its colony morphology and tendency to form abundant chlamydospores, but since strains typically form few macroconidia it may not be recognised and hence go unreported. In comparison with other Discolor taxa such as F. culmorum or F. graminearum, the species is relatively uncommon. This view is supported by the infrequent receipt of strains for identification at IMI. Reliable information on its distribution and biological activities is, therefore, relatively sparse. Although the fungus occurs on cereals (74, 7805) and can be isolated from cattle feed (Skrinjar et al., 1995) its ability to produce mycotoxins is currently unreported. Immobilised cells of F. flocciferum have been investigated to extract phenol from toxic wastes (Anselmo et al., 1989; Anselmo & Novais, 1992a, b). Decomposition of xylan and cellulolytic activity on filter paper has been studied (Domsch & Gams, 1969). The fungus was reported to have antagonistic activity in vitro towards Gaeumannomyces graminis and Rhizoctonia solani (Domsch & Gams, 1968).
 
Description type:Non-original description 
Description:Fusarium flocciferum Corda, Sturm's Deutschl. Flora 2: 17, 1828.
Fusarium flocciferum Corda f. 1 Raillo, Fungi of the genus Fusarium (Moscow), p. 215, 1950.
Teleomorph unknown. According to Wollenweber & Reinking (1935) this closely resembles the anamorph of Gibberella heterochroma Wollenw., Ann. Mycol. 15: 52, 1917. Colonies on PSA with slow to moderate growth rates, 40-60 mm diam. after 10 days, with initially white, floccose aerial mycelium, later darkening to pink and assuming a dry, powdery, speckled appearance; reverse initially white or pale pink, later becoming brown with some vinaceous red pigment, the margin remaining pale, unpigmented; sporulation sparse in most strains, sometimes arising only after 3-4 weeks incubation, forming in scattered pale orange sporodochia in the agar surface. Conidiogenous cells monophialides, borne on irregularly branching clusters of cells, cylindrical, 15-25 x 3-4 µm, with periclinal thickening and small collarette. Macroconidia 3-5-septate, 3-septate (16-) 34 (-40) x 3-3,5 µm, 4-septate (30-) 38 (-45) x 3,5-4 µm, 5-septate (36-) 43 (-60) x 3,5-4 µm, falcate, widest medianly, tapering evenly towards the ends, apex drawn to a slightly extended, sharp point, basal cell distinctly pedicellate. Chlamydospores forming abundantly, often in dense, irregular clusters, becoming pale brown, smooth or roughened, 8-18 µm.
Hosts: Isolated from soil. Also occurs on the roots of a wide range of plants, including temperate cereals (Hordeum, Triticum), legumes (Lupinus, Pisum, Vicia), cucurbits (Cucumis sativus), and others such as carrot (Daucus carota) and beet (Beta vulgaris); sometimes occurs in association with nematodes.
Disease: Not regarded as an aggressive pathogen, but in association with nematodes may cause root lesions, damping-off, root, tuber or bulb rots. Reported to cause disorders of cultivated mushroom beds. Occasionally causes skin infections of animals (one IMI record from crocodile's tail).
Geographical distribution: Widespread but infrequent, apparently more common in temperate regions. Reported from Asia: Bhutan, China, India, Iran, Turkey; Australasia: New Zealand; Europe: Denmark, Germany, The Netherlands, Poland, Turkey (W), UK; North America: Canada, USA.
Physiological specialization: None reported.
Transmission: Conidia are dispersed locally by water flow and splash droplets. Chlamydospores may be transported by movement of soil or infected plant debris. It may also be seed-borne (71, 1568).
Literature: Anselmo, Cabral & Novais, Applied Microbiology and Biotechnology 31: 200-203, 1989; Anselmo & Novais, Water Science and Technology 25: 161-168, 1992a; Anselmo & Novais, Biotechnology Letters 14: 239- 244, 1992b; Domsch & Gams, Phytopathologische Zeitschrift 63: 165-176, 1968; Domsch & Gams, Soil Biology and Biochemistry 1: 29-36, 1969; Skrinjar, Stubblefield, Stojanovic & Dimic, Acta Veterinaria Hungarica 43: 259-267, 1995; Wollenweber & Reinking, Die Fusarien, ihre Beshreibung, Schadwirkung und Bekämpfung. Paul Parey, Berlin, 1935.

 
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