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Mould saprotroph fungi belong to surface microflora of wheat seeds. Grain may be infected in maturing period under high humidity conditions at low temperature, but more often moulds develop during storage. A. fumigatus forms light-violet or brown mycelium. Conidiophores are 300 by 2-8 um in size, with bladder-like inflation on top, 20 to 30 um in diameter. Sterigmas are mononuclear, located on upper part of bladder-like inflation. Conidia are mononuclear, ellipsoidal or spherical, smooth or spinose, 2.5 to 3 um in size. A. glaucum forms friable yellow-green mycelium. Conidiophores are unbranched, bloated on top, bearing sterigmas that branch off radially and diverge at apices like chains. Conidia are spherical, bristly, green, 7 to 15 mkm in diameter. P. cyclopium forms mycelium of light-blue to dark-green colors. Conidiophores are single, 200-400 by 3-3.5 um in size, rough, sometimes smooth, with one or more branchlets. 4 to 8 sterigmas in fascicle are 7-10 by 2.2-2.8 um in size, with truncated top. Conidia are spherical, 3.3 to 4 um in diameter or elliptical, 3.3-4 by 2.5 um in size. P. glaucum forms green-gray mycelium; conidiophores have branched racemule; apical branches bear chains of small-sized round uncolored spores (2 to 4 um in diameter each). T. roseum forms dense felt mycelium; conidiophores are unbranched, bearing bulb-shaped and bicellular spores on top, 12-18 by 8-10 um in size. M. mucedo forms dark-red mycelium with black dots (sporangia); sporangiophores are brown, gathered in fascicles (3 to 5), 4 mm in height. Sporangium is spherical, 100 to 200 um in diameter; spores are unicellate, spherical or ellipsoidal, 8-14 by 6-11 um in size, with gray wrinkled surface. Spores of mould fungi are preserved in granaries, and under favorable conditions may cause mass infection of seeds.
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