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66 THE BBITISH SMUT FUNGI This species has usually been designated U. bromivora (Tul.) Fisch. v. Waldh., but an examination of the type specimen of U. hullata Berk, on Triticum (Agropyron) scabrum from New Zealand confirms the aption of Fischer (1937) in reducing U. bromivora to a synonym of U. bullata. The type of Cintractia patagonica Cooke & Massee, a smut described on B. unioloides from Patagonia and subsequently reported in Lincolnshire on the same host grown from imported seed, was found to agree with U. bullata. Spore germination. Schroeter (1887) described the promycelium as cylindrical, spindle-shaped, readily falling away from the spore, becoming septate, and producing sporidia from the ends and sides. These, which were usually two-celled like the promycelia, gave rise to unicellular sporidia. Brefeld (1883) germinating spores from B. secalinus figured fusions between cells of the promyceUum and between the unicellular sporidia (Fig. 2 i). Plowright (1889) confirming these observations found that spores collected in June germinated freely in September and the general experience has been that spores of this species germinate easily. McAlpine (1911) also described and figured germination, following Brefeld in regarding it as a distinct type. Hiittig (1931) found, however, that the manner of growth varied with temperature. At 20° C. two-ceUed sporidia are cut off as described by previous workers but at 25° C. a four-celled promyceUum is formed with terminal and lateral sporidia (the so-called violacea type see p. 70). Subsequent development is characterized by the abundant production of sporidia by budding as in U. hordei and U. avenae and scanty mycelial growth (KoBs, 1943). Bauch (1925) working with six collections of U. bromivora [V. bullata] noted several variations of the method of germination. While some spores produced a normal four-ceUed promycelium others developed two promycelia each of which was two-ceUed, while others had one three-celled and one one-celled promycelium. The sporidia were always unicellular and fusion was governed by a single pair of factors. In certain collections neutral strains were discovered which could be distinguished from the normal so-called sexual strains by the special growth form of the colonies. Hirschhom (1941 b), working with collections of spores from species of Hordeum and Bromus, detected slight differences in the size and number of promycelial cells which might be diagnostic for physiologic races. Infection of the host arid racial specialization. Extensive inoculation experiments have shown that infection takes place at the seedling stage (Liro, 1924; Fischer, 1940 b).. Using 44 collections from 36 species of Agropyron, Bromus, Elymus, Festuca, Hordeum, and Sitanion, Fischer (1940 b) detected eight physiologic races by their reactions on 14 differential hosts. They include the races on Bromus secalinus and B. mollis which Liro (1924) raised to specific rank. Ustilago maydis (DC.) Corda Maize Smut [Lycoperdon zeae Beckmann, 1768.] Uredo segetum var. mays-zeae de CandoUe, 1805. Uredo maydis de CandoUe, Flor. franc, vi, p. 77, 1815. Uredo zeae Sehweinitz, 1822. Ustilago zeae Unger, 1836.
THE BRITISH SMUT FUNGI 67 Ustilago maydis (DC.) Corda, Icones Fung., v, p. 3, 1842. Vstilago mays-zeae Magnus, 1895. Sori in the inflorescence and other aerial parts of the host as irregular sweUings less than 1 cm. to more than 10 cm. in length, at first limited by a white or cream membrane of host and fungus tissue. Spore mass powdery, very dark sepia. Spores globose or sub-globose to ellipsoidal, epispore bluntly echinulate, 8-12 fi diam. On Zea mays. Occasionally recorded in southern England. Exsiccati: Cooke, Fung. Brit. Exsicc., i, 433; ii, 431. Spore germination, which has been described by Brefeld (1895) and a number of other workers, takes place in nutrient solution at any time of the year. Terminal and lateral uninucleate sporidia are borne on a four-celled promycehum, singly or in simple or branched chains. Sporidial fusion occurs only under certain conditions (see p. 42). Infection of the host. Brefeld (1895) first demonstrated the localized infection of maize by U. maydis in contrast to the systemic infection of several other cereal smuts. The fungus can penetrate any part of the plant where the tissue is meristematic. Walter (1934) described the direct penetration of the epidermal wall and found that infection might arise either from the promycelium or from germinating sporidia. Chlamydospores and sporidia are distributed by wind and are very resistant to low temperature and to desiccation. The smut can ^ multiply and live for some time as a saprophyte in soil (Piemeisel, 1917). Chlamydospores retained viabihty in pure sand for eight years (Kornfeld, 1937) and were not always destroyed by silage (Perlet, 1938). In the United States dry weather conditions are most conducive to infection (Immer & Christensen, 1928). Racial specialization. Ustilago maydis, a heterothalhc species, comprises an indefinite number of biotypes differing in pathogenicity and other characters (Christensen, 1931; Christensen et al., 1929; Hirschhorn & Hirschhom, 1939). Isolations from a single smut gall differed in their reactions on inbred fines of maize under artificial methods of inoculation (Eddins, 1929 a), but collections of smut spores from separate geographical areas were often aHke in pathogenicity when tested on selfed fines of maize under field conditions. Eesistance and suseeptibUity are governed by genetic factors. Flint varieties are more susceptible than dent varieties (Hayes et al., 1924), but rpsistailt selections can be found in most types of maize, and breeding for resistance offers the most promising method of control (Immer & Christensen, 1925; Immer, 1927; Immer & Christensen, 1931; Christensen & Johnson, 1935). Ustilago striiformis (Westend.) Niessl Stripe Smut of Grasses Ustilago salvei Berkeley & Broome, 1850.^ ' Berkeley & Broome (Notices of British Fungi, No. 482) described V. salvei on Dactylia glomerata collected by Rev. T. Salwey, St. Martin's, Guernsey. De Toni {Sacc. Syll., va, p. 485, 1888) listed U. salvei as a synonym of U. striiformis, and Liro (1922) used the name for a smut on D. glomerata which he considered to be distinct from V. striiformis. Examination of the Berkeley and Broome type in Herb. Kew. shows the host to be Holcus lanatus and the fungus to be V. striiformis. As the niles stand at present XJ. salvei Berk. & Br. appears to be the valid name for the fungus now widely known as V. striiformis, but we agree with Stevenson (Plant Dis. Beptr, xxx, p. 53,1946) in not advocating the adoption of the former name.
Page 1 and 2:
THE BRITISH SMUT FUNGI ^ (USTILAGIN
Page 3:
FOREWORD THIS volume was started wh
Page 6 and 7:
6 PBEFACE We also acknowledge the b
Page 9 and 10:
INTRODUCTION THE smut fungi, which
Page 11 and 12:
INTRODUCTION H of bushels of wheat
Page 14 and 15:
FIG. 1. Vstilago avenae on Arrhenat
Page 16:
^^ THE BBITISH SMUT FUNGI Young hea
Page 19 and 20: BIOLOGY 15 less than the normal, in
Page 21 and 22: BIOLOGy 17 and united with it, fina
Page 23 and 24: BIOLOGY 19 eermination in a collect
Page 25 and 26: BIOLOGY 21 genus, and the manner of
Page 27 and 28: BIOLOGY 23 species of Entyloma, and
Page 29 and 30: 3036^ BIOLOGY 25 in others. Dickins
Page 31 and 32: CYTOLOGY THE discovery of nuclei in
Page 33 and 34: GENETICS INCOMPATIBILITY KNIEP'S di
Page 35 and 36: GENETICS • 31 direction of growth
Page 37 and 38: GENETICS 35 when a few sporidia fro
Page 39 and 40: GENETICS 37 lines retained their di
Page 41 and 42: TECHNIQUE COLLECTION AND EXAMINATIO
Page 43 and 44: TECHNIQUE 41 be undesirable. Weak a
Page 45 and 46: TECHNIQUE 43 in one season (see p.
Page 47 and 48: TECHNIQUE 45 barley with loose smut
Page 49 and 50: TECHNIQUE 47 (1939), Holton & Heald
Page 51 and 52: TECHNIQUE 49 Allen's, modification
Page 53 and 54: CLASSIFICATION THE morphological ch
Page 55 and 56: THE BRITISH SMUT FUNGI MOST of the
Page 57 and 58: FIG. 2. Spore geimination in Ustila
Page 59 and 60: THE BRITISH SMUT FUJJGI 57 from one
Page 61 and 62: THE BRITISH SMUT FUKGI 59 of exsert
Page 63 and 64: THE BRITISH SMUT FUNGI 61 noticeabl
Page 65 and 66: THE BRITISH SMUT FUNGI 63 Evidence
Page 67: THE BRITISH SMUT FUNGI 65 winter in
Page 71 and 72: THE BRITISH SMUT FUlJGI 69 material
Page 73 and 74: THE BRITISH SMUT FUNGI 71 results o
Page 75 and 76: THE BRITISH SMUT FUNGI 73 TTstilago
Page 77 and 78: THE BRITISH SMUT FUNGI 75 Species i
Page 79 and 80: " TJSE BRITISH SMUT FUNGI 77 Ustila
Page 81 and 82: THE BKITISH SMUT FUNGI 79 On Carex
Page 83 and 84: THE BRITISH SMUT FUNGI 81 Exsiccati
Page 85 and 86: THE BRITISH SMUT FUNGI 83 Tilletia
Page 87 and 88: THE BRITISH SMUT FUNGI 85 bunt ball
Page 89 and 90: THE BEITISH SMUT FUNGI 87 globose t
Page 91 and 92: THE BRITISH SMUT FUNGI 89 FIG. 13.
Page 93 and 94: FIG. 15. Spore geimination in Taboi
Page 95 and 96: FIG. 17. Spore germination in Urocy
Page 97 and 98: THE BRITISH SMUT FUNGI 95 separate
Page 99 and 100: THE BRITISH SMUT FUNGI 97 8ori in t
Page 101 and 102: THE BRITISH SMUT FUNGI 99 Urocystis
Page 103 and 104: 30390 THE BRITISH SMUT FUNGI 101 pr
Page 105 and 106: FIG. 20. Spore geimination in Entyl
Page 107 and 108: THE BRITISH SMUT FUNGI 105 Sori in
Page 109 and 110: On Ranunculus ficariae and B. scler
Page 111 and 112: THE BRITISH SMUT FUNGI 109 Infectio
Page 113 and 114: THE BKITISH SMUT FUNGI 111 [Sporidi
Page 115 and 116: THE BRITISH SMUT FUNGI 113 Ustilago
Page 117 and 118: REFEEENCES 115 BBETT, M. A. (1940).
Page 119 and 120:
REFERENCES 117 ^ DniON WESTON, W. A
Page 121 and 122:
REFERENCES 119 GRIFFITHS, MAEIOK A.
Page 123 and 124:
REFERENCES 121 HtjTTiG, W. (1933).
Page 125 and 126:
REFEBENCES 123 LiMBOtruN, E. J. (19
Page 127 and 128:
REFERENCES 125 NOBLE, E. J. (1934).
Page 129 and 130:
REFERENCES 127 RoDENHiSEE, H. A., &
Page 131 and 132:
BEFERENCES 129 STAKMAK, E. C, XCEEN
Page 133 and 134:
EEFEEENCES 131 WAXTBE, J. M. (1934)
Page 135 and 136:
INDEX to generic and specific names
Page 137 and 138:
Muscari Ustilago vaillantii, 59 Myo
Page 139 and 140:
Ustilago ficuum Reich., 113 —flps
Page 141 and 142:
2i}:y0 ANDHRA PRADESH AGRICULTURAL
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