Cercospora oryzae. [Descriptions of Fungi and Bacteria].

1974 ◽  
Author(s):  
J. L. Mulder
Keyword(s):  
Geographical Distribution ◽  
Lateral Spread ◽  
Stages Of Growth ◽  
Brown Leaf Spot ◽  
White Leaf ◽  
Brown Leaf ◽  
Panicum Repens ◽  
Linear Leaf ◽  
Axis Parallel ◽  
The Tropics

Abstract A description is provided for Cercospora oryzae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Oryza saliva. DISEASE: Narrow brown leaf spot of rice. The fungus has been reported on Panicum repens (Plant Disease Reporter 54: 272, 1970). The linear leaf lesions are 2-10 mm long, usually up to 1-1.5 mm wide, the long axis parallel to that of the leaf; centre dark brown with the border fading as the outer margin is reached. Lesions on the sheath are similar to those on the leaf, whilst those on the glumes are shorter and tend to lateral spread. On susceptible cvs. the leaf lesions are wider and lighter brown whereas on resistant ones they are narrow and a more uniform dark brown. Symptoms are usually extensive during the later stages of growth and should not be confused with those caused by Ramularia oryzae Deighton & Shaw (white leaf streak; 40, 104). GEOGRAPHICAL DISTRIBUTION: Widespread in the tropics and S. and S.E. USA (CMI Map 71, ed. 3, 1967). TRANSMISSION: No studies reported.

Pseudocercospora timorensis. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
S. Little
Keyword(s):  
Sweet Potato ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Ipomoea Batatas ◽  
Leaf Surface ◽  
Solomon Islands ◽  
Leaf Spots ◽  
Brown Leaf Spot ◽  
Water Splash ◽  
Brown Leaf

Abstract A description is provided for Pseudocercospora timorensis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Ipomoea batatas (sweet potato), I. biloba, I. campanulata, I. cordofana, I. muricata, I. peltata, I. setifera.DISEASE: Leaf spot or brown leaf spot of sweet potato. Small circular lesions first form on the leaf borders and tips before spreading over the leaf surface. These leaf spots enlarge becoming brown to dark brown in colour with a verruculose surface. The larger leaf veins may delimit the spots. GEOGRAPHICAL DISTRIBUTION: Africa: most countries; Asia: Hong-Kong, India, Indonesia, Malaysia, Taiwan; Australasia: Fiji, Papua New Guinea, Solomon Islands; North America: West Indies (St Lucia). TRANSMISSION: Presumably by wind-borne and water-splash dispersed conidia.

Mycosphaerella henningsii. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
S. Little
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Surface ◽  
Lower Leaf Surface ◽  
Leaf Spots ◽  
Brown Leaf Spot ◽  
Water Splash ◽  
Brown Leaf ◽  
Leaf Veins ◽  
Severe Infections

Abstract A description is provided for Mycosphaerella henningsii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Manihot esculenta (cassava, manioc), M. glaziovii (manicoba, ceara rubber), M. palmata and, under laboratory conditions, Ipomoea sp. (36: 82). DISEASE: Brown leaf spot, sometimes referred to as leaf blight of cassava. At first the lesions start as small circular greenish yellow spots. These enlarge and become angular as they are delimited by the major leaf veins; on the upper leaf surface the spots are tan to light tan, 1-8 mm diam. with a dark brown slightly raised border. Minor leaf veins crossing the leaf spot are seen as black necrotic lines. In severe infections the leaf spots are surrounded by a yellow halo caused by a toxin produced by the advancing mycelium (Teri et al., 1977). On the lower leaf surface the spots are less distinct. Eventually the lesions may coalesce, and cause premature defoliation. GEOGRAPHICAL DISTRIBUTION: Generally found wherever cassava is cultivated (Teri, 1977). Africa: most countries; Asia: Jordan, Philippines, Sri Lanka, Thailand; North America: Dominican Republic, USA (Florida); South America: Bolivia, Brazil, Colombia, Peru, Venezuela. TRANSMISSION: Probably by wind-borne and water-splash dispersed conidia. During the dry season the fungus survives on the crop debris.

Chaetoseptoriawellmanii. [Descriptions of Fungi and Bacteria].

1985 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Phaseolus Vulgaris ◽  
South America ◽  
Central America ◽  
Geographical Distribution ◽  
Vigna Unguiculata ◽  
Natural Infection ◽  
Vigna Sinensis ◽  
Brown Leaf Spot ◽  
Water Splash ◽  
Brown Leaf

Abstract A description is provided for Chaetoseptoriawellmanii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Phaseolus vulgaris and Vigna unguiculata (=Vigna sinensis). DISEASE: Brown leaf spot of Phaseolus and Vigna. At first lesions appear as small purplish brown or chocolate spots with distinct margins. With the progress of infection spots enlarge, occasionally coalesce, turn reddish-brown and become rounded or irregular reaching up to 1 cm wide with lighter or whitish centres. Older lesions become distinct on both surfaces with distinct margins prominent on the upper surfaces with pycnidia scattered within the spots. GEOGRAPHICAL DISTRIBUTION: Central America (Guatemala, El Salvador) South America (? Colombia). TRANSMISSION: Little information exists on natural infection and how the disease spreads in the field. It is possible that conidia could be dispersed by water splash and the fungus might survive in crop debris left from previous years.

Cercospora malayensis. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
S. Little
Keyword(s):  
Sierra Leone ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
West Indies ◽  
Leaf Surface ◽  
Euphorbia Pulcherrima ◽  
Leaf Spots ◽  
Brown Leaf Spot ◽  
Brown Leaf ◽  
Rain Splash

Abstract A description is provided for Cercospora malayensis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Hibiscus abelmoschus (musk mallow), H. cannabinus (deccan hemp), H. esculentus (okra), H. fisculatus, H. mutabilis, H. sabdariffa, H. suranensis, Euphorbia pulcherrima, Sphaeralcea cisplaniina. DISEASE: Leaf spot or brown leaf spot of Hibiscus spp. The first symptoms are yellowish patches on the leaf surface. These then become necrotic and gradually expand into irregular greyish brown leaf spots with dark brown to purple borders, surrounded by a pale yellow halo. Ultimately the necrotic areas become shrivelled and crack (30, 445). GEOGRAPHICAL DISTRIBUTION: The fungus is found wherever Hibiscus is cultivated (Chupp & Sherf, 1960). Africa: Ethiopia, Ghana, Mauritius, Sierra Leone, South Africa, Sudan, Tanzania, Uganda, Zimbabwe; Asia: Borneo, India, Indonesia, Japan, Malaysia, Philippines; Australasia: Fiji, Papua New Guinea; North America: West Indies (Jamaica, Trinidad, Cuba); South America: Colombia, Venezuela. TRANSMISSION: Presumably by wind-borne and rain-splash dispersed conidia.

Septoria chrysanthemella. [Descriptions of Fungi and Bacteria].

1967 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Tagetes Patula ◽  
Leaf Spots ◽  
Chrysanthemum Indicum ◽  
Previous Season ◽  
Brown Leaf Spot ◽  
Water Splash ◽  
Brown Leaf ◽  
Black Leaf Spot

Abstract A description is provided for Septoria chrysanthemella. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Chrysanthemum indicum, C. japonicum, C. morifolium, C. parthenium. Also by inoculation on C. azaleanum, C. koreanum, C. leueanthemum, C. segetum, C. roseum, Tagetes patula, Centaurea cyanus (Punithalingam & Wheeler, 1965; Schneider, 1959). DISEASE: Formerly known as brown leaf spot or blight (Halsted, 1891; Cavara, 1892; Salmon, 1907; Moore, 1959) but now referred to as the black leaf spot of chrysanthemum (Hemmi & Nakamura 1927; Waddel & Weber, 1963) in order to distinguish the symptoms from those produced by Septoria obesa (CMI Descript. 139). The first visible leaf symptom is a small discrete necrotic spot. This gradually develops into a circular or elliptical spot seldom irregular, about 5-10 mm wide, at first dark brown, then turning black. Leaf spots of a purple to brown colour, with a distinct brown margin are not uncommon. The disease appears in susceptible chrysanthemum plants of all ages, first on the lower leaves and then gradually progressing upwards. This is a disfiguring disease and in a severe attack all leaves wither resulting in premature defoliation. GEOGRAPHICAL DISTRIBUTION: Africa (Ethiopia, Kenya, Malawi, Mauritius, Mozambique); Asia (China, Formosa, Japan, Pakistan, Philippines); Australasia (Australia, New Zealand); Europe (Austria, Azores, Bulgaria, Cyprus, Czechoslovakia, Denmark, France, Germany, Iceland, Italy, Norway, Portugal, Rumania, Spain, Yugoslavia, U.S.S.R.); North America (Canada, U.S.A.), Central America (Costa Rica, Cuba). (Literature; Herb. IMI). TRANSMISSION: Dimock & Allyn (24: 192) suggested the pathogen may survive the winter in the soil in infected debris from the previous season. The fungus may be disseminated by water splash or by mechanical means as with S. obesa.

Drechslera sacchari. [Descriptions of Fungi and Bacteria].

1971 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
French Guiana ◽  
Toxin Production ◽  
Saccharum Officinarum ◽  
Pennisetum Purpureum ◽  
Leaf Spots ◽  
Lemon Grass ◽  
Axis Parallel ◽  
Young Leaves ◽  
The Tropics

Abstract A description is provided for Drechslera sacchari[Bipolaris sacchari]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Saccharum officinarum and also reported causing diseases in Pennisetum purpureum (Napier or elephant grass) and Cymbopogon citratus[Cymbopogon nardus] (lemon grass). DISEASE: Eye spot and seedling blight of sugarcane. Small reddish spots, surrounded by a straw-coloured halo, develop on the leaves; conspicuous on young leaves, becoming 5-12 × 3-6 mm, longer axis parallel to the main veins, coalescing. These spots may develop long chlorotic streaks running towards the leaf tip, 60-90 cm long and possibly due to toxin production. Germinating seed may be killed 12-14 days from sowing and severely attacked young plants show a top rot. On lemon grass the leaf spots have pale centres with a dark purple border, 4-10 × 1.5-2 mm (20: 229). Older leaves of Napier grass are attacked most, severe outbreaks causing death (17: 753; 21: 258). GEOGRAPHICAL DISTRIBUTION: Widespread in the tropics and subtropics (CMI Map 349, 2nd ed. 1968). Additional records not yet mapped: Cambodia, French Guiana, Panama, Salvador and Senegal. TRANSMISSION: Presumably through air-dispersed conidia; seed-borne infection also occurs (36: 350).

scholarly journals First Report of the Occurrence of White Leaf Streak in Louisiana Rice

Plant Disease ◽  
1998 ◽  
Vol 82 (11) ◽  
pp. 1282-1282 ◽  
Author(s):  
A. K. M. Shahjahan ◽  
M. C. Rush ◽  
J. P. Jones ◽  
D. E. Groth
Keyword(s):  
United States ◽  
Leaf Spot ◽  
The United States ◽  
Research Station ◽  
Conidial Suspension ◽  
Cultivated Rice ◽  
First Report ◽  
Brown Leaf Spot ◽  
White Leaf ◽  
Brown Leaf

White leaf streak, caused by Mycovellosiella oryzae (Deighton and Shaw) Deighton (syn. Ramularia oryzae), was found in Louisiana rice. The symptoms closely resemble those of narrow brown leaf spot caused by Cercospora janseana (Racib.) O. Const. (syn. C. oryzae (Miyake)), and it is difficult to distinguish between these two diseases. Initially both produce similar elongated light brown lesions, but later the lesions of white leaf streak become wider with a whitish center and are surrounded by a narrow light brown margin (2,3). The disease was first observed at the Rice Research Station, Crowley, LA, in 1996 on older leaves of the cultivar Lemont at maturity. Leaves containing the unusual lesion types were placed in a moist chamber and incubated at 28°C for 5 days. Abundant conidia were produced and the fungus was isolated on acidified potato dextrose agar (APDA) by single spore isolation and by plating infected tissues after surface sterilization in 40% Clorox for 10 to 15 min. The colonies grew slowly on APDA and were dark gray in color. The conidia formed in branched chains or singly. They were hyaline, cylindrical with tapering ends and a thick hilum; 0 to 3 septate, and 15 to 35 m long (1,3). Pathogenicity tests were conducted in the greenhouse on the Lemont and Cypress rice cultivars by spraying a conidial suspension (103–4 conidia per ml) onto leaf blades at boot stage. Conidia were produced by growing the fungus on PDA for 10 to 14 days. Inoculated plants were placed inside a humid chamber in a greenhouse and maintained for 4 to 5 weeks. Many elongated lesions similar to those observed in the field were produced 3 to 4 weeks after inoculation. Reisolation from these lesions yielded M. oryzae. With the same methods, 45 cultivars and lines were inoculated to determine their reactions to this disease. Most of the cultivars grown in the southern United States were moderately susceptible or susceptible to white leaf streak. Foreign cultivars tested, including BR-7, BR-11, Cica-4, Cica-6, Cica-7. Cica-8, Cica-9, Oryzica llanos, Rax clear, Teqing, and Tetep, were resistant. In 1997, the disease was found prevalent on many cultivars grown at the Rice Research Station, Crowley, LA. As symptoms of both white leaf streak and narrow brown leaf spot were sometimes observed on the same leaf; it is possible that the disease has been present, but not identified as a separate disease because of the similarity of the symptoms of the two diseases. A thorough survey is necessary to determine the extent of its occurrence and further studies are necessary to determine its yield loss potential. At present it appears to be a minor problem for Louisiana rice. White leaf streak has previously been recorded from Papua New Guinea on cultivated Oryza sativa, and from the Solomon Islands, Sabah, Nizeria, and Sierra Leone on cultivated O. glabberima Steudel and on wild perennial rice O. berthii A. Chev. (2). This is the first report of white leaf streak on cultivated rice in the United States. References: (1) F. C. Deighton. Mycol. Pap., CMI 144:1,1979. (2) F. C. Deighton and D. Shaw. Trans. Br. Mycol. Soc. 43: 515, 1960. (3) B. C. Sutton and A. K. M. Shahjahan. Nova Hedwigia 25:197, 1981.

Recurrent Phenotypic Selection for Resistance to Brown Leaf Spot in Smooth Bromegrass 1

Crop Science ◽  
1986 ◽  
Vol 26 (3) ◽  
pp. 533-536 ◽  
Author(s):  
Clyde C. Berg ◽  
Robert T. Sherwood ◽  
Kenneth E. Zeiders
Keyword(s):  
Leaf Spot ◽  
Phenotypic Selection ◽  
Smooth Bromegrass ◽  
Brown Leaf Spot ◽  
Brown Leaf ◽  
Selection For

Cercostigmina protearum var. protearum. [Descriptions of Fungi and Bacteria].

1999 ◽  
Author(s):  
P. M. Kirk
Keyword(s):  
South Africa ◽  
Geographical Distribution ◽  
Leaf Spots ◽  
Brown Leaf

Abstract A description is provided for Cercostigmina protearum var. protearum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. DISEASE: Causing round or sometimes irregular, pale brown or greyish-brown leaf spots 5-17 mm diameter. HOSTS: Leucospermum conocarpum, Protea. TRANSMISSION: By air-borne conidia. GEOGRAPHICAL DISTRIBUTION: AFRICA: South Africa.

Gibberella zeae. [Descriptions of Fungi and Bacteria].

1973 ◽  
Author(s):  
C. Booth
Keyword(s):  
Geographical Distribution ◽  
Secondary Infection ◽  
Brown Rot ◽  
Gibberella Zeae ◽  
Infested Soil ◽  
Foot Rot ◽  
Seedling Blight ◽  
Water Droplets ◽  
Ascospore Discharge ◽  
The Tropics

Abstract A description is provided for Gibberella zeae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Wheat, maize, barley, carnations and other ornamentals; also reported infecting Lycopersicon, Pisum, Trifolium and Solanum DISEASE: Seedling blight, pre-emergence and post-emergence blight, root and foot rot, brown rot, culm decay, head or kernel blight (scab or ear scab) of wheat, maize, barley and other cereals. Leaf and flower rot of carnations and other ornamentals. Also reported infecting species of Lycopersicon, Pisum, Trifolium and Solanum. GEOGRAPHICAL DISTRIBUTION: Worldwide on maize and rice in the tropics. Wheat, oats, barley and rye in temperate regions. TRANSMISSION: By planting infected or infested seeds or by planting in infested soil. Secondary infection occurs widely by water droplets under moist conditions or by ascospore discharge.

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