File:Leptothyrium pomi.jpg

Identifier: fungousdiseases00dugg Title: Fungous diseases of plants, with chapters on physiology, culture methods and technique Year: 1909 (1900s) Authors: Duggar, Benjamin M. (Benjamin Minge), 1872-1956 Subjects: Fungi in agriculture Fungi Plant diseases Publisher: Boston, New York [etc.] : Ginn and company Contributing Library: University of British Columbia Library Digitizing Sponsor: University of British Columbia Library

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Text Appearing Before Image: merely roughening the surface of the cuticle. The blotches are irregular inoutline, sometimescoalescing intolarge areas. Thespecks, as the nameindicates, are small,circular, dark col-ored flecks associ-ated in groups, andsometimes distrib-uted over largeareas. A network of ra-diating olive-brownor fuliginous hyphaemade up of more orless barrel-shapedcells constitute theblotch. Cell fusions and cell aggregations are common. On theother hand, the specks areat first dense aggregatesof rather light colored hy-phae, and from such specksdelicate hyphae may betraced to similar neighbor-ing spots or to blotches.A mature speck becomesshining black and dry.Then the central portionbreaks away and is pre-sumably the source of newinfections. No spore formhas been found accom-panying this phase. Both, r r 1 Fig. i88. Leptothyrium Pomi: Develop- types of fungus have, ^^^^^ ^^ tycnidia from Pycnosclerotia however, been followed (Photograph by B. F. Floyd) Fig. 187. Fly Speck and Sooty Blotch of Apple

Text Appearing After Image: FUNGI IMPERFECTl 369 throughout the autumn and winter and careful sections made atdifferent times. In the case of the blotch, as the season advances,the cell aggregates may develop a definite sclerotial-like body(November in Missouri), By March this body has differentiatedinto a pycnidium (Fig. 188) 25 to loo/x in diameter, of theLeptothyrium type, bearing hyaline, elliptical spores. The lattermeasure 12-14 x 2-3 /-t. CHAPTER XIII HEMIBASIDIOMYCETES I. USTILAGINALES Brefeld, O. Die Brandpilze, I. Unters. a. d. Gesammtgeb, d. Mykologie 5 : I-220. pis. 1-13. 1883.Brefeld, O., u. Falck, R. Ibid. 13: 1-75. pls. 1-2. 1905.Clinton, G. P. North American Ustilagineas. Proc. Boston Soc. Nat. Hist. 31 : 329-529. 1905.Dangeard, p. a. Recherches histologiques sur la Famille des Ustilagin^es. Le Botaniste 3 : 240-281, 1892.De Bary, A. Die Brandpilze. 144 pp. 8ph. 1853.DiETEL, P. Ustilagineae und Tilletiineae. Natiirl. Pflanzenfam. (Engler u. Prantl, Red.) 1 (Abt. i * *): 2-24. Jigs. 1-13.Fischer d

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