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94 THE BRITISH SMUT FUNGI<br />

ribbons. Spore mass powdery, black. Spore halls irregularly globose, 14-26 jti<br />

diam., each composed of one or two (occasionally three) spores completely surrounded<br />

by a layer of yeUowish-tinted sterile cellsl mostly 7-10 /i diam., but<br />

frequently rather disorganized to give a ridged effect. Spores irregularly globose,<br />

reddish-brown, smooth, 12-14 (rarely up to 16) fj. diam.<br />

On Agropyron pungens, A. repens, Arrhenatherum\elatius.<br />

May-June. England (Surrey), Scotland.<br />

Spore germination of the smut on grasses is unknown. Spore balls from wheat<br />

germinate on water in three to five days, producing a short thick promycehum<br />

with an apical cluster of three to five or more hyahne cylindrical sporidia<br />

(Fischer & Hirschhorn, 1945 a).<br />

Infection of the host occurs at the seedhng stage. The fungus persists for several<br />

years in perennial grasses (Fischer & Holton, 1943). Underground buds of<br />

Agropyron repens were infected experimentally but not those of Carex, Phleum,<br />

Poa, or Agrostis species (Liro, 1938).<br />

Racial specialization. The following species of grasses in the United States are<br />

more or less susceptible to the stripe smut of wheat: Agropyron caninum, A.<br />

dasystachyum, A. desertorum, A. inerme, A. repens, A. semicostatum, A. spicatum,<br />

A. trachycaulum, Elymus canadensis, E. glaucus, E. triticoides, and Hordeum<br />

jubatum var. caespitosum. Rye appears to be immune but one variety of wheat<br />

(KanredxHard Federation C.I. 10092) is slightly susceptible to Urocystis<br />

agropyri from grasses. Three out of four collections of spores from grasses were<br />

physiologically distinct (Fischer & Holton, 1943). In South Africa and in<br />

Australia the stripe smut from wheat failed to infect grasses (Verwoerd, 1929;<br />

Jarrett, 1932).<br />

Two physiologic races of the wheat stripe smut were distinguished by their<br />

reactions on certain Oro X Federation selections (Holton & Johnson, 1943), and<br />

12 races were recognized in China where varietal resistance and its mode of<br />

inheritance have been studied (Shen, 1934; Yu, Hwang, & Tsiang, 1936; Yu,<br />

Wang, & Fang, 1945). Work on the resistance of wheat varieties to stripe smut<br />

has also been done in Australia (Pridham & Dwyer, 1930; Limbourn, 1931;<br />

Jarrett, 1932.; Millikan & Sims, 1937), in South Africa (Verwoerd, 1929), and in<br />

the United States (Tisdale, Duncan, & Leighty, 1923).<br />

Urocystis anemones (Pers.) Winter Anemone Smut<br />

Uredo anemones Persoon, Synopsis meth. Fung., p. 233, 1801.<br />

Gaeoma pompholygodes Schlechtendal, 1826, fide Saccardo, 1886.<br />

Polycystis pompholygodes (Schlecht.) LeveiUe, 1846.<br />

Polycystis anemones (Pers.) LeveiUe, 1847.<br />

Urocystis pompholygodes (Schlecht.) Rabenhorst, 1864.<br />

Urocystis anemones (Pers.) Winter in Rabenh. Krypt. Flor., i (1), p. 123,1881.<br />

Tuburcinia anemones (Pers.) Liro, 1922.<br />

Sori in the leaves and stems as blister-like swellings beneath the epidermis which<br />

ruptures to expose the spores. Spore mass powdery, black. Spore balls irregular,<br />

16-32 fi diam., each composed of one spore (occasionally two or three) partially<br />

surrounded by yellowish sterile cells, 6-14 fx. diam., which not infrequently

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