Mycosphaerella arachidis. [Descriptions of Fungi and Bacteria].

1974 ◽  
Author(s):  
J. L. Mulder
Keyword(s):  
Geographical Distribution ◽  
Arachis Hypogaea ◽  
Leaf Spot ◽  
Leaf Surface ◽  
Seed Transmission ◽  
Diurnal Periodicity ◽  
Leaf Surfaces ◽  
Carry Over

Abstract A description is provided for Mycosphaerella arachidis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Arachis hypogaea. DISEASE: Early leaf spot of groundnut: also called tikka with Mycosphaerella berkeleyi (CMI Descript. 412). Lesions circular, 1-10 mm diam., reddish-brown to black on the upper leaf surface and lighter shades of brown on the lower. Distinct chlorotic halos develop early on the upper surface. The lesions tend to be larger than those of M. berkeleyi and the dark stroma of the latter is absent. The conidia form on both leaf surfaces, the conidiophores being somewhat diffuse. Severe attacks cause defoliation (13, 74; 17, 651; 35, 342). GEOGRAPHICAL DISTRIBUTION: Widespread with host (CMI Map 166, ed. 3, 1966). TRANSMISSION: In India the air dispersed conidia showed a diurnal periodicity with a peak at 1000 h (50, 1524), and in USA most conidia were trapped at 1100-1500 h; rain increased numbers (Smith & Crosby, Phytopathology 63: 703-707, 1973). Carry-over occurs in host debris and seed transmission seems unimportant.

Mycosphaerella berkeleyi. [Descriptions of Fungi and Bacteria].

1974 ◽  
Author(s):  
J. L. Mulder
Keyword(s):  
Geographical Distribution ◽  
Arachis Hypogaea ◽  
Leaf Spot ◽  
Seed Transmission ◽  
Diurnal Periodicity ◽  
Late Leaf Spot ◽  
Conidial State ◽  
Carry Over

Abstract A description is provided for Mycosphaerella berkeleyi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Arachis hypogaea. DISEASE: Late leaf spot of groundnut; also called tikka with Mycosphaerella arachidis (CMI Descript. 411). The circular lesions, up to c. 8 mm diam., become very dark brown or black with the chlorotic halos on the upper surface being less distinct and developing later than those of M. arachidis. Mycosphaerella herkeleyi symptoms are most clearly identified by the distinct dark stroma of the conidial state which develops on the undersurface of the leaf; M. arachidis forms conidia on both surfaces and has no such stroma. Severe attacks cause defoliation (13, 74; 17, 651; 35, 342). GEOGRAPHICAL DISTRIBUTION: Widespread with host (CMI Map 152, ed. 3, 1967). TRANSMISSION: In India the air dispersed conidia showed a diurnal periodicity with a peak at 1000 h (50, 1524). Carry over occurs in host debris (41, 76) and seed transmission seems unimportant.

Drepanopeziza ribis. [Descriptions of Fungi and Bacteria].

1979 ◽  
Author(s):  
C. Booth
Keyword(s):  
New Zealand ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Surface ◽  
Leaf Surfaces ◽  
Water Borne

Abstract A description is provided for Drepanopeziza ribis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Ribes spp. DISEASE: Causes leaf spot or anthracnose of currants and gooseberries. Symptoms consist of small, dark brown, round or irregular spots scattered over the leaf surface. They may coalesce if numerous. Infected leaves may turn yellow (especially in gooseberry) and fall. Minute greyish acervuli develop in lesions on upper and lower leaf surfaces. Lesions may also occur on petioles and peduncles, where they are elongated, and on fruit. GEOGRAPHICAL DISTRIBUTION: Europe, N. America, Japan, Australia and New Zealand (CMI Map 187, ed. 2, 1967). TRANSMISSION: By water-borne conidia produced from the Gloeosporidiella state on leaf lesions. Apothecia are produced from saprophytic growth on fallen diseased leaves and they produce air-borne ascospores in spring.

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.

Septoria lactucae. [Descriptions of Fungi and Bacteria].

1972 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Geographical Distribution ◽  
Seed Coat ◽  
Lactuca Sativa ◽  
Leaf Spot ◽  
Early Symptoms ◽  
Leaf Surfaces ◽  
A Minor

Abstract A description is provided for Septoria lactucae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Lactuca sativa. DISEASE: A minor leaf spot of lettuce (Lactuca sativa). Early symptoms are small, numerous, irregularly outlined, chlorotic spots beginning on the outer leaves. They enlarge, becoming brown or somewhat silvery, sometimes with a chlorotic halo, and shot-holes develop. Pycnidia, which may not be conspicuous, are found on both leaf surfaces. Infection spreads to the younger leaves and flowers in severe attacks (20: 193; 21: 182). GEOGRAPHICAL DISTRIBUTION: Widespread (CMI Map 485, ed. 1, 1972). TRANSMISSION: By seed, pycnidia can be found embedded in the seed coat (41: 267).

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.

Septoria helianthi. [Descriptions of Fungi and Bacteria].

1970 ◽  
Author(s):  
P. Holliday
Keyword(s):  
Helianthus Annuus ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Seed Treatment ◽  
Seed Transmission ◽  
Adaxial Surface ◽  
Young Leaves

Abstract A description is provided for Septoria helianthi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Helianthus annuus, Helianthus grosseserratus and Helianthus rigidus. DISEASE: Leaf spot of sunflower. Yellowish spots up to 1.5 cm develop over the whole lamina, gradually turning necrotic and becoming almost black. The numerous pycnidia are mostly on the adaxial surface. The lesions have a polygonal outline, being sharply delimited by the veins. Infection may begin on the cotyledons and young leaves, spreading to later developing leaves. Severe attacks lead to defoliation and loss in yield. GEOGRAPHICAL DISTRIBUTION: Fairly widespread in E. Europe and the U.S.S.R. in Asia, China, Japan, Australia (Qd.); E. and S. Africa, N. America (CMI Map 468, ed. 1, 1970). TRANSMISSION: Overwintering occurs in host debris. Seed treatment is recommended although seed transmission does not appear to have been demonstrated. Introduction of the fungus into Hungary may have been via seed (43, 2013).

Ramularia galegae. [Descriptions of Fungi and Bacteria].

1986 ◽  
Author(s):  
J. Ingham
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Surface ◽  
Wind Dispersal ◽  
Galega Officinalis

Abstract A description is provided for Ramularia galegae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOST: Galega officinalis: Goat's rue. DISEASE: Leaf spot of G. officinalis. Lesions tend to be elongated, being restricted by larger veins, but several infections together can give the lesions an irregular appearance. Small tufts of conidiophores can be seen on either leaf surface. Sporulation is known to occur in October. GEOGRAPHICAL DISTRIBUTION: Europe (France, Italy, Romania). TRANSMISSION: By wind dispersal of air-borne conidia.

Cylindrosporium concentricum. [Descriptions of Fungi and Bacteria].

1977 ◽  
Author(s):  
B. C. Sutton
Keyword(s):  
New Zealand ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
South Australia ◽  
Seed Transmission ◽  
Oil Seed ◽  
Oil Seed Rape

Abstract A description is provided for Cylindrosporium concentricum[Pyrenopeziza brassicae]. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Brassica spp. (cabbage, cauliflower, broccoli, brussel sprouts, oil seed rape, swedes). DISEASE: Light leaf spot of Brassicae. GEOGRAPHICAL DISTRIBUTION: Europe (UK, Ireland, Netherlands, Germany, Denmark, Norway, Portugal, Rumania, Latvia); Asia (Japan, Philippines); Australia (South Australia, Tasmania); New Zealand. (CMI Map 193, ed. 2, 1975). TRANSMISSION: By splash-dispersed air-borne conidia. No seed transmission has been demonstrated.

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.

Mycovellosiella cajani. [Descriptions of Fungi and Bacteria].

1979 ◽  
Author(s):  
J. M. Waller
Keyword(s):  
East Africa ◽  
Sierra Leone ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
West Indies ◽  
Pigeon Pea ◽  
Carry Over ◽  
A Minor

Abstract A description is provided for Mycovellosiella cajani. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Cajanus, Callicarpa, Desmodium and Solanum verbascifolium. DISEASE: Causes a minor leaf spot of pigeon pea. The spots are usually small, round with an indefinite margin and are usually pale brown in the centre with a darker border. GEOGRAPHICAL DISTRIBUTION: East Africa, Sierra Leone, Nigeria, West Indies, Venezuela, Mauritius, India, Pakistan, Burma and Taiwan. TRANSMISSION: By air-borne conidia and may carry over on crop debris.

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