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Remarks (public):For a complete description including images see 
Remarks (internal):Fusarium avenaceum is extremely variable particularly with regard to the appearance of the cultures. The shape of the macroconidia and the absence of both mycelial and conidial chlamydospores separate it from F. culmorum (CMI Descript. 26) and F. equiseti. Fusarium avenaceum is not as widespread as the two other related species causing blight on cereals, Gibberella zeae (F. graminearum) and F. culmorum but may cause serious losses as a pre-emergence and seedling blight in cooler climates as in U.S.S.R. to spring wheat and in Scotland to oats (24: 184; 32: 181). The influence of temperature on the disease has been studied by De Haan (1937). Other factors influencing infection include soil pH (32: 181) and the concentration of CO2 in both soil and air (2: 384; 17: 250).Control measures consist of crop rotation and sanitation, with particular reference to covering crop residues thoroughly and the use of seed treatment with organo-mercurial compounds. Resistant varieties have been reportedfor lucerne (22: 27); potatoes (23: 312; 25: 182; 31: 626); barley (32: 181) and wheat (15: 789); 19: 335; 24: 184; 32: 181).
Description type:Non-original description 
Description:Fusarium avenaceum (Corda: Fr.) Sacc., Sylloge Fungorum 4: 713, 1886.
= Fusisporium avenaceum Fr., Syst. Myc. 3: 444, 1832.
Colour of cultures variable but peach (light coral red) appears to be most common and often underlies the more dominant pigments such as red, olive buff or pomegranate purple. Blue or violet pigments absent. Mycelium generally white floccose or tinged with peach. Sporodochia absent, developing spasmodically or abundant, giving rise to orange pustules as the macroconidia develop; in pionnotial-forming strains mycelial formation is suppressed and cultures assume a slimy adpressed appearance with a deep ochraceous salmon colouration. Microconidia absent. Macroconidia fusiform to falcate with incurved pointed tips, and when formed from simple conidiophores in the aerial mycelium are distinctly pedicellate, 3-7-septate when mature and orange in mass; 0-1-septate 10- 15 x 3,5 µm, 3-septate 21-38 x 3,5 µm, 4-6-septate 44-70 x 4-5 µm. Chlamydospores absent in mycelium, rarely present in conidia.
Hosts: A large number of plant species representing more than 150 genera in the following families. including the Gramineae, are attacked: Caryophyllaceae, Compositae, Coniferae, Cruciferae, Cucurbitaceae, Euphorbiaceae, Juglandaceae, Leguminosae, Liliaceae, Linaceae, Moraceae, Onagraceae, Palmae, Rosaceae, Rutaceae, Salicaceae, Scrophulariaceae, Solanaceae, Sterculiaceae, Theaceae, Thymeliaceae, Umbelliferaceae, Valerianaceae, Vitaceae. Also recorded on Equisetaceae, Polypodiaceae and insects Wollenweber & Reinking (1935), Gordon (34: 258; 38: 581; 40: 89) and Herb. IMI.
Diseases: Causing damping-off of a large number of nursery seedlings, and a seedling blight, 'spring yellows', foot and root rot, premature ripening and blight of ears of wheat, barley, oats and rye; and on maize cobs: a wilt of flax, a basal rot of carnation cuttings and root rots of lucerne and sweet clover; also storage rots of potato, sugar-beet, carrot and dahlia as well as fruit of apple, pear, cocurbits, citrus, walnut and tomato.
Distribution: Widespread in the temperate zone but also found in parts of the humid tropics.
Physiological specialization: Tu (1929) found form 2 constantly more virulent than form 1 on most vars. of wheat, barley and oats. The opt. temp. for growth of form 1 (27°C) was higher than that of form 2 (22°C). Virulent and avirulent forms have also been reported on lucerne by Cormack (1937, 1951) and on cereals, lupin and carnation by Schneider (1958). In the U.S.S.R., the pathogenicity of various strains have been found correlated with the amount of amine nitrogen accumulated in culture, the most virulent showing the least (15: 457; 16: 31; 18: 97).
Transmission: Seed-borne on a wide range of hosts [Noble et. al. (An Annotated List Of Seed-Borne Diseases, Commonw. Mycol. Inst. Kew, pp. 159, 1958), Gordon (34: 258)], also soil-borne, and from mycelium or wind-borne spores produced on over-wintered crop residues.
Literature: For general studies on the taxonomy and variability of Fusarium avenaceum see Wollenweber & Reinking, Die Fusarien, Berlin, pp. 355, 1935; Snyder & Hansen, Amer. J. Bot. 32(10): 657-666, 1945; Schneider, Phytopath. Z. 32(1): 95-126; 32(2): 129-148, 1958: for studies on cereals see Bennett, Ann. Appl. Biol. 15: 213- 244 1928; Tu, Phytopathology 19(2): 143-154, 1929; Guyot, Rev. Path. Veg. 21(4): 143-186, 1934; De Haan, Phytopath. Z. 10(3): 235-305, 1937; Bakshi, Indian Phytopath. 4(2): 162-169, 1951; for studies on potatoes see McLean & Walker, J. Agric. Res. 63(9): 495-525, 1941; Moore, Ann. Appl. Biol. 32(4): 304-309, 1945; McKee, Ann. Appl. Biol. 41(3): 417-434, 1954; and on lucerne see Cormack, Canad. J. Res. Sect. C 15(11): 493-510, 1937; Canad. J. Bot. 29(1): 32-45, 1951.
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