Pyrenophora avenae. [Descriptions of Fungi and Bacteria].

1973 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
Primary Infection ◽  
Secondary Infection ◽  
Seedling Blight ◽  
Secondary Spread ◽  
Leaf Stripe ◽  
Blight Of Oats

Abstract A description is provided for Pyrenophora avenae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Oats (Avena spp.). DISEASE: Leaf stripe, blotch or spot and seedling blight of oats. Seed-borne infection produces a range of seedling symptoms from pre-emergence death to slight spotting or streaking of coleoptiles. Mycelial infection of emerging leaves causes distortion and spotting. Inoculum from primary leaves causes secondary spread to upper leaves, producing light reddish-brown irregular streaks or blotches. Spikelet drop (42, 543) and stem-break (36, 641) may also occur when the disease is severe. GEOGRAPHICAL DISTRIBUTION: Widespread; occurs throughout most oat-growing areas. CMI Map 105, ed. 2, 1966, and in addition in Queensland, Egypt, Angola and Colombia. TRANSMISSION: Primary infection appears to be entirely by seed-borne inoculum, either as conidia or more particularly as mycelium in the outer layers of the seed. Secondary infection is by air-borne conidia. Soil-borne inoculum appears to be unimportant.

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.

Venturia pirina. [Descriptions of Fungi and Bacteria].

1974 ◽  
Author(s):  
A. Sivanesan
Keyword(s):  
Leaf Litter ◽  
Geographical Distribution ◽  
Primary Infection ◽  
Secondary Infection ◽  
Apple Scab ◽  
Black Spot ◽  
Eriobotrya Japonica ◽  
Venturia Pirina ◽  
Young Growth

Abstract A description is provided for Venturia pirina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Principally on pear (Pyrus communis) and other Pyrus spp., also recorded from Eriobotrya japonica (loquat) (Herb. IMI). DISEASE: Causes scab or black spot of pear, which results in loss of quantity and quality of fruit. The disease attacks shoots, buds, leaves and fruit, symptoms and aetiology being very similar to those of apple scab caused by V. inaequalis on Malus spp. (CMI Descript. 401). Dark, more or less circular scabs are produced on leaves and fruit, often with some growth distortion. Infection of young wood is more common than with apple scab and causes pale brown blister-like lesions which burst to release conidia in the following year. GEOGRAPHICAL DISTRIBUTION: Worldwide in temperate and subtropical regions wherever pears are grown (see CMI Map 367, ed. 2, 1968). TRANSMISSION: Epidemiology is similar to that of apple scab. The overwintering saprophytic perithecial stage on leaf litter releases airborne ascospores in spring which infect young growth, and secondary infection by conidia dispersed during wet summer weather also occurs. Overwintering lesions on young wood are more frequent than with apple scab and conidia produced by these in the spring can be an important source of primary infection (46, 2061; 47, 849).

Cochliobolus miyabeanus. [Descriptions of Fungi and Bacteria].

1971 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Oryza Sativa ◽  
Geographical Distribution ◽  
Primary Infection ◽  
French Polynesia ◽  
Brown Spot ◽  
Seed Infection ◽  
Seedling Blight ◽  
Late Afternoon ◽  
Leaf Spots ◽  
Cochliobolus Miyabeanus

Abstract A description is provided for Cochliobolus miyabeanus. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Oryza sativa and other species of Oryza. DISEASE: Brown spot and seedling blight of rice. Oval leaf spots up to 1 cm long, at first usually brown, sometimes purplish, later forming white to grey centres, spots may coalesce and leaves wither. Glumes may be spotted, becoming velvety with sporulation. Infected seed is shrivelled and discoloured; coleoptiles bear lesions which can also occur on the roots of seedlings. GEOGRAPHICAL DISTRIBUTION: Widespread (CMI Map 92, ed. 3, 1966). Records not yet mapped: Angola, Cambodia, Chad, France (S.), French Polynesia, Hong Kong, Laos, Malawi, Nepal, Rhodesia. TRANSMISSION: Seed infection is important (mycelium remaining viable for up to 3 yr) and is probably responsible for most of the primary infection in young crops (9: 556; 34: 104). Grain is directly attacked and kernels in the flowering and milk stages are more susceptible than those in the soft dough and mature stages (45, 2834; 46, 317). Conidia are air-dispersed showing a diurnal periodicity with a max. in the late afternoon (43, 1017; 48, 3486).

Pyrenophora graminea. [Descriptions of Fungi and Bacteria].

1973 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
Secondary Infection ◽  
Diseased Plant ◽  
Grain Production ◽  
Leaf Stripe ◽  
The World ◽  
Pyrenophora Graminea ◽  
Leaf Shedding ◽  
Dry Out ◽  
Seedling Infection

Abstract A description is provided for Pyrenophora graminea. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Barley and other Hordeum spp. Also, occasionally, on oats, wheat and rye. DISEASE: Causes leaf stripe of barley. Severe seedling infection can cause stunting and post-emergence death, but symptoms are not usually apparent until later, when long, chlorotic or yellow stripes on leaves and sheaths appear. Most leaves of a diseased plant are usually affected. Dark brown streaks develop later in the stripes, which eventually dry out and cause leaf shedding. Ears may not emerge or be deformed and discoloured. Grain production by infected plants is severely restricted. GEOGRAPHICAL DISTRIBUTION: Widespread distribution; occurs in most barley-growing areas of the world. TRANSMISSION: Seed-borne (49, 1342) usually by mycelium in the pericarp. Perithecia are uncommon, but overwintering sclerotia on crop debris have been reported from Russia (42, 13). Secondary infection by conidia is apparently important only for floral infection and subsequent seed contamination.

Setosphaeria rostrata. [Descriptions of Fungi and Bacteria].

1978 ◽  
Author(s):  
K. H. Anahosur
Keyword(s):  
Central America ◽  
Geographical Distribution ◽  
Primary Infection ◽  
Foot Rot ◽  
Ear Rot ◽  
Damping Off ◽  
Seedling Blight ◽  
Stalk Rot ◽  
Long Period ◽  
Leaf Spots

Abstract A description is provided for Setosphaeria rostrata. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On graminicolous hosts and on Amaryllis, Carica, Cucumis, Jasminum, Nicotiana and from soil. DISEASE: Causes leaf spots, foot rot of wheat (56, 2446), seedling blight of Cynodon (46, 2051), leaf blight of Eleusine (46, 1263), damping-off of sugarcane seedlings (50, 1562l), stalk rot (53, 2167) and ear rot of maize, blackening of seeds and seed germination failure (34, 91; 51, 2435). GEOGRAPHICAL DISTRIBUTION: Africa (Mauritius, Nigeria, S. Africa, Sudan); Asia (China, India, Israel, Pakistan); Central America (Puerto Rico); Europe (Denmark); North America (USA). TRANSMISSION: The fungus is soil-borne and can survive saprophytically for a long period (43, 398). Also seed transmissible (51, 2435). Conidia are produced abundantly in moist conditions and are dispersed by wind and rain, and act as a source of primary infection. Many grasses and weeds act as collateral hosts (39, 321).

Pyrenophora teres. [Descriptions of Fungi and Bacteria].

1973 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
Primary Infection ◽  
Secondary Infection ◽  
Growing Season ◽  
Pyrenophora Teres ◽  
Net Blotch ◽  
Floral Bracts

Abstract A description is provided for Pyrenophora teres. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Primarily barley, but also occurs sporadically on wheat, oats and many other Gramineae. DISEASE: Causes net blotch of barley. Primary infection occurs from seed-borne inoculum and produces lesions on the first leaves, which are at first pale but develop into dark spots or streaks later. Secondary infection on older leaves produces pale brown blotches, in which is a network of dark brown lines; these may later coalesce to form irregular leaf stripes. Lesions also occur on the floral bracts. On other hosts the reticulate pattern of the lesions is usually absent. GEOGRAPHICAL DISTRIBUTION: Worldwide; occurs in most barley-producing countries (CMI Map 364, ed. 2, 1968). TRANSMISSION: The disease can be seed-borne as mycelium or conidia, but can also over-winter on crop debris. Perithecia are common on old barley stubble in the spring and ascosporic inoculum can produce much infection (49, 116). Secondary infection by air-borne conidia occurs throughout the growing season.

Venturia populina. [Descriptions of Fungi and Bacteria].

1976 ◽  
Author(s):  
A. Sivanesan
Keyword(s):  
North America ◽  
Geographical Distribution ◽  
Primary Infection ◽  
Secondary Infection

Abstract A description is provided for Venturia populina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOST: Populus spp. DISEASE: Blight or dieback of poplars. GEOGRAPHICAL DISTRIBUTION: Europe and North America. TRANSMISSION: By ascospores and conidia (41, 106). Primary infection by ascospores and secondary infection by conidia.

Ramulispora sorghi. [Descriptions of Fungi and Bacteria].

1978 ◽  
Author(s):  
K. H. Anahosur
Keyword(s):  
South America ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Primary Infection ◽  
Leaf Blight ◽  
Disease Spread ◽  
Leaf Stripe ◽  
Infection Disease

Abstract A description is provided for Ramulispora sorghi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Sorghum almum, S. bicolor, S. caffrorum, S. halepense, S. purpureosericeum, S. saccharatum, S. sudanense, S. vulgare. DISEASE: Leaf spot, leaf stripe or sooty stripe. Elongated, elliptical or spindle shaped spots 5-14 × 1-2 cm with straw coloured necrotic centres and reddish-purple or tan borders appear on leaves and leaf sheaths. Spots coalesce to cause a leaf blight. Black sclerotia, which can be brushed off easily, are abundant on necrotic areas (Tarr, 1962). GEOGRAPHICAL DISTRIBUTION: Africa (W. Africa, Ethiopia, Rhodesia, Sudan, Tanzania, Uganda, Zambia); Asia (China, India, Pakistan); Australia (Queensland); South America (Argentina); USA (Alabama, Nebraska, Texas). TRANSMISSION: Sclerotia and sporodochia on crop debris produce conidia in damp weather thus acting as sources of primary infection. Disease spread is favoured by wind and rain under warm and moist conditions which favour sporulation (Tarr, 1962). Sclerotia and sporodochia remain viable up to 2 years (Rawla et al., 1974). The fungus is also transmitted through seeds (21, 286; 47, 807).

scholarly journals Reinfection as a cause of complications and relapses in scarlet fever wards

1937 ◽  
Vol 37 (2) ◽  
pp. 153-171 ◽  
Author(s):  
V. D. Allison ◽  
W. A. Brown
Keyword(s):  
Scarlet Fever ◽  
Primary Infection ◽  
Secondary Infection ◽  
Clinical Signs ◽  
Late Complications ◽  
Isolation Method ◽  
Fever Patient ◽  
The Third ◽  
Serological Type ◽  
Mode Of Transmission

1. The term “reinfection” has been defined as the secondary infection of a scarlet fever patient during hospitalization withStr. pyogenesbelonging to a serologically different type from that producing the primary infection.2. Of forty-seven scarlet fever patients nursed in a multiple-bed ward and swabbed twice weekly during their period of isolation, thirty-three (70.2 per cent) became reinfected with a serological type ofStr. pyogenesdifferent from that causing the primary disease.3. In fifteen out of the thirty-three patients reinfected, the reinfection was “latent”, i.e. gave rise to no clinical signs, while in the remaining eighteen the reinfection was “manifest”, i.e. was accompanied by clinical signs or complications.4. Patients nursed in cubicles or in a ward confined to infections with a single serological type did not show reinfection; their convalescence was progressive and there were no late complications.5. The majority of complications occurring during the third week of hospitalization and subsequently, in multiple-bed wards devoted to scarlet fever, are due to reinfection.6. Most reinfections occur during the third week in hospital at a time when patients are as a rule convalescent from their primary infection.7. The most frequent mode of transmission of reinfection appears to be by direct contact of patient with patient.8. Ten instances of “relapse” in scarlet fever (only three in the present series) are quoted; in all of them the patients were nursed in multiple-bed wards. In each instance the “relapse” coincided with the isolation of a fresh serological type ofStr. pyogenesfrom the throat, and must therefore be regarded as a second attack of scarlet fever.9. The various systems of nursing patients in isolation hospitals are discussed and it is suggested that scarlet fever patients should be cubicle-nursed if possible. Failing this they should be nursed by the bed-isolation method in multiple-bed wards. By setting aside small wards it might be possible to keep together patients who are all infected by the same serological type ofStr. pyogenes; the number of such wards would vary with the number (usually three or four) of epidemic types current at the time.

Erwinia mallotivora. [Descriptions of Fungi and Bacteria].

1981 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Surface ◽  
Bacterial Leaf Spot ◽  
Secondary Spread ◽  
Shoot Blight ◽  
Mallotus Japonicus ◽  
Rain Splash

Abstract A description is provided for Erwinia mallotivora. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOST: Mallotus japonicus (Euphorbiaceae). DISEASE: Bacterial leaf spot. The disease starts as water-soaked spots on the newly developing leaves in May and June. The spots tend to form close to the main veins. They enlarge and become angular as they are restricted by the veins, becoming dark brown, and often with a chlorotic halo about 1 mm wide. Spots may coalesce and kill the leaf, and shoot blight may also occur. Under humid conditions bacteria may exude on to the leaf surface. GEOGRAPHICAL DISTRIBUTION: Japan. TRANSMISSION: Unknown, but presumably rain splash plays a part at least in secondary spread.

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