nmm sP
nmm sP
nmm sP
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
THE BRITISH SMUT FUlJGI 69<br />
material from AlopexMrus pratensis, Deschampsia caespitosa, and Dactylis<br />
glomerata infected the hosts named by sowing contaminated seed. Negative<br />
results were obtained with other grasses. Davis (1926) showed that stripe smut<br />
infects Phleum pratense at the seedling stage. The disease wiU persist for several<br />
years in perennial grasses, but infected plants tend to die under adverse conditions<br />
such as drought (Leach, Lowther, & Ryan, 1946).<br />
Bacial specialization. This species has been variously subdivided by Liro (1924),<br />
Ciferri (1938), Fischer (1940 a), and other workers an(i in this country it has been<br />
confused with the closely related but possibly distinct U. macrospora (q.v.). A<br />
stripe smut with larger spores (14-17 n) on Phalaris has been distinguished as<br />
U. echinata Schroet. but the one British collection (Sridge of Dun, Angus, coll.<br />
R. W. G. Dennis, 26.vii.43, Herb. Kew.) of stripe smut of this host examined does<br />
not differ morphologically from U. striiformis.<br />
Ustilago macrospora Desm.<br />
Ustilago macrospora Desmazieres, PI. Crypt, franc. No. 2127, 1850.<br />
Differs from TJ. striiformis (q.v.) in the spores \\rhich are spherical to ellipsoidal<br />
but frequently somewhat elongated or angular, yeUow-hrown, coarseJj<br />
echinulate or verrucose to papillate, at times somewhat reticulate or striate,<br />
11-18 (av. 13-5-14-5) [j. diam.<br />
On Agropyron repens, A. junceum, Bromus erectus, and Calamagrostis canescetis.<br />
May-Aug. England (Norfolk, Surrey), Guernsey, S(>otland.<br />
The first British record is by V. J. Chapman (Tratis. Norf. Nonvich Nat. Sac,<br />
xiii, p. 302, 1932) on A. junceum, Scolt Head, Norfolk [Herb. Kew.].<br />
Spore germination. Unknown.<br />
Racial specialization. It is doubtful if the stripe smut of Calamagrostis distinguished<br />
as U. calamagrostis (Fuckel) Clinton is a morphologically distinct species.<br />
The one British collection (Wheatfen Broad, Norfolk, coU. E. A. ElHs, 9.vu.44,<br />
Herb. I.M.I. 32329) on C. canescens does not differ from U. macrospora from<br />
other grasses in this country.<br />
*** Spores reticulate<br />
Ustilago vinosa Tul.<br />
Uredo vinosa Berkeley in litt. to Tulasne [nom. nud.].<br />
Ustilago vinosa Tulasne, Ann. Sci. nat., Bot., Ser. 3, vii, p. 96,1847.<br />
Sori involving the flower parts within the perianth, which is frequently inflated.<br />
Spore mass powdery, pinkish purple. Spores globose to sub-globose, tinted<br />
violet, delicately reticulate (reticulations 1-0 fi or slightly less in diam.), 6-10<br />
(mostly 7-8) n diam. [Type specimen in Herb. Kew.]<br />
On Oxyria digyna.<br />
July. England (Cumber!.), Scotland (Forfarshire). Uncommon.<br />
Spore germination. Sporidia develop from a four-celled promycelium, bud, and<br />
fuse readily in nutrient solution (Brefeld, 1883).<br />
Infection of the host. Unknown. Mycelium is said to be perennial in the root<br />
stock (Schellenberg, 1911).