Ramulispora sorghicola. [Descriptions of Fungi and Bacteria].

1978 ◽  
Author(s):  
K. H. Anahosur
Keyword(s):  
Sorghum Bicolor ◽  
Geographical Distribution ◽  
Wild Species ◽  
Leaf Spot ◽  
Lower Surface ◽  
Infected Leaf ◽  
Small Water ◽  
Leaf Tissues ◽  
Upper Volta

Abstract A description is provided for Ramulispora sorghicola. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Sorghum bicolor, S. halepense, S. nitidum, S. vulgare, Sorghum spp. (wild). DISEASE: Leaf spot. Small water-soaked lesions develop into oval to elliptical spots up to 7 × 3 mm, delimited by veins, with dark red or tan border up to 1 mm wide. Spots become irregular by 2-3 spots coalescing, with pinkish grey to straw necrotic centres. A few black sclerotia are found on the lower surface of roots. GEOGRAPHICAL DISTRIBUTION: Africa (Ethiopia, Nigeria, Malawi, Upper Volta); Asia (India, Indonesia, Pakistan). TRANSMISSION: The fungus can survive in the fragments of infected leaf tissues which remain on the ground and produce masses of conidia in damp weather which are disseminated by rain and wind. Sclerotia also survive and produce conidia in damp weather (Harris, 1960; Tarr, 1962). Wild species of sorghum act as collateral hosts.

Mycosphaerella macrospora. [Descriptions of Fungi and Bacteria].

1974 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
South Africa ◽  
North America ◽  
Middle East ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Tissue ◽  
Infected Leaf ◽  
Perfect State ◽  
Small Water ◽  
America South

Abstract A description is provided for Mycosphaerella macrospora. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Iris, Glodiolus; also recorded from Narcissus, Freesia and Hemerocallis. DISEASE: Leaf spot or blotch of iris. Initially, symptoms appear as small water-soaked spots soon turning brown and enlarging to produce oval lesions with a greyish centre and dark brown margin. These become irregular and coalesce and may destroy much of the leaf tissue. The disease is most serious after flowering and on the distal portions of leaves. GEOGRAPHICAL DISTRIBUTION: Europe, North America, South Africa, Australia and Middle East. TRANSMISSION: Conidia are dispersed by wind and rain. Overwintering infected leaf debris is an important source of spring inoculum. The perfect state appears to be uncommon.

scholarly journals First Report of Leaf Spot Disease on Schisandra chinensis Caused by Phoma glomerata in China

Plant Disease ◽  
2012 ◽  
Vol 96 (2) ◽  
pp. 289-289 ◽  
Author(s):  
X. Wang ◽  
J. Wang ◽  
J. Gao ◽  
L. Yang
Keyword(s):  
Leaf Spot ◽  
Sequence Data ◽  
Leaf Spot Disease ◽  
Infected Leaf ◽  
Its Sequence ◽  
Schisandra Chinensis ◽  
Water Control ◽  
First Report ◽  
Spot Disease ◽  
Leaf Tissues

Schisandra chinensis (Turcz.) Baill is a perennial liana belonging to the Schisandra genus of the family Magnoliaceae, which is cultivated in China as an important medicinal plant. In the summer of 2008, we observed a previously unknown foliar disease on the schisandras in Jingyu and Antu counties and the cities of Ji'an and Hunchun in Jilin Province. Symptoms appeared on the apex, margin, and center of leaves. The infection initially manifested as pale brown, small, necrotic spots on the leaves. Subsequently, these lesions became grayish brown in the center and dark brown with slight protuberances at the margins. Finally, these lesions developed concentric rings with a clear boundary separating them from the healthy tissue, were round to elliptical or irregular in shape, and had a diameter of 3 to 5 mm. In severely infected leaves, these spots eventually covered the entire leaf. Black spots (pycnidia) were produced on the infected leaf tissues in a humid environment. Fungus from infected leaf tissues was isolated on potato dextrose agar. The cultures were initially pale brown and turned dark green with age. Embedded pycnidia were generally formed after 5 days. The pycnidia were agglutinating, globose to subglobose, and measured 60.0 to 212.0 × 33.6 to 268.0 μm. Abundant conidia (4.06 to 7.2 × 1.65 to 3.53 μm) exhibiting zero to three oil droplets were produced by an 8-day-old colony; these conidia were ovoid or ellipsoidal, colorless, and aseptate; they were similar to conidia of Phoma glomerata. The internal transcribed spacer (ITS) sequence of rDNA of the isolated pathogenic strain (PG11; GenBank Accession No. GU724511) had 100% identity to P. glomerata (GenBank Accession No. HM769279). Therefore, the pathogen was identified as P. glomerata (Corda) Wollenw. & Hochapfel on the basis of morphology and ITS sequence data. To validate Koch's postulates, schisandra leaves were spray inoculated with a 2.5 × 105 conidia/ml suspension of the isolated pathogen. An equal number of healthy plants were inoculated with sterile water (control). After inoculation, 10 plants were covered with plastic bags for 3 days and maintained in a growth chamber at 25°C. After 8 days, all inoculated plants showed symptoms identical to those observed on the schisandra leaves infected in the field, whereas the controls did not show any symptoms. Reisolation of the fungi from lesions of inoculated leaves confirmed that the causal agent was P. glomerata. Diseases caused by P. glomerata have been reported on some plants (1,2). However, to our knowledge, this is the first report of leaf spot disease caused by P. glomerata on S. chinensis in China as well as in the world. References: (1) J. S. Chohan et al. Trans. Br. Mycol. Soc. 75:509, 1980. (2) T. Thomidis et al. Eur. J. Plant Pathol. 131:171,2011.

Pseudomonas lachrymans. [Descriptions of Fungi and Bacteria].

1967 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Central America ◽  
Cucumis Sativus ◽  
Geographical Distribution ◽  
Southern Africa ◽  
Leaf Spot ◽  
Crop Residue ◽  
Fruit Rot ◽  
Small Water ◽  
Rain Splash ◽  
Pseudomonas Lachrymans

Abstract A description is provided for Pseudomonas lachrymans. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Cucumis sativus and C. anguria. It may also attack C. melo var. inodorus (26: 140) and some other cucurbits. Elliott (31: 105) lists 10 hosts, all in the Cucurbitaceae. DISEASE: Angular leaf spot of cucumber. Small water-soaked spots appear on the leaves, petioles, stems, and fruits. On leaves they enlarge and become angular as they are delimited by veins They become tan to brown and the necrotic centres may fall out. On petioles, stems, and fruit spots develop white crusty bactenal exudate. A fruit rot develops if the bacteria penetrate deeply. GEOGRAPHICAL DISTRIBUTION: North and parts of Central America, most of Europe, U.S.S.R., China, Japan, W. Australia, Israel, southern Africa. (CMI Map 355, ed. 2, 1964). TRANSMISSION: The pathogen is seed-borne and infects the cotyledons dunng germination. It can overwinter on infected crop residue in the soil and has been found viable in dry leaf matenal after two and a half years (36: 677). The bacteria are carried from plant to plant within a crop by rain splash and probably by insects (Carsner, 1918; 31: 272). Workers can also spread the disease, particularly when foliage is wet with rain or dew (35: 810).

Ascochyta sorghi. [Descriptions of Fungi and Bacteria].

1979 ◽  
Author(s):  
E. Punithalingam
Keyword(s):  
Sorghum Bicolor ◽  
Host Plant ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Crop Residues ◽  
Leaf Spots ◽  
Wet Weather ◽  
Indistinct Margin

Abstract A description is provided for Ascochyta sorghi. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Sorghum bicolor and wild sorghums. DISEASE: Rough leaf spot of sorghum. On leaves symptoms appear as small circular to oblong light coloured spots with well defined reddish margin. Older lesions become broadly elliptic, greyish to yellow brown or purplish red, reaching 4-9 × 8-14 mm. Lesions often merge with one another to form large irregular necrotic areas up to 12.5 × 2.5 cm and the whole leaves may be killed. The variety of host plant mostly determines whether the leaf spots have a distinct red margin or an indistinct margin (Tarr, 1962; Edmunds & Zummo, 1975). Lesions may also occur on leaf sheaths and sometimes on leaf stalks. The disease appears to be severe on young plants whilst older plants have been reported to be resistant to attack (13, 746). GEOGRAPHICAL DISTRIBUTION: Africa (Eritrea, Gambia, Ghana, Nigeria, Senegal, Sudan, Tanzania, Zaire); Asia (Burma, India); Europe (Italy); N. America (USA, Alabama, Georgia); USSR. TRANSMISSION: Infection has been claimed to be spread by air-borne conidia in wet weather or heavy dews and also by insects (Singh et al., 1951; Tarr, 1962; Edmunds & Zummo, 1975). The fungus has been reported to be carried over on crop residues of sorghum and debris in the soil (Singh et al., 1951; Edmunds & Zummo, 1975).

Cercospora carbonacea. [Descriptions of Fungi and Bacteria].

1987 ◽  
Author(s):  
S. Little
Keyword(s):  
Puerto Rico ◽  
North America ◽  
South America ◽  
Sierra Leone ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
West Indies ◽  
Lower Surface ◽  
Leaf Spots ◽  
Rain Splash

Abstract A description is provided for Cercospora carbonacea. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Dioscoria spp. DISEASE: Leaf spot of yams. Causes fairly large, 5-20 mm, angular leaf spots, which are usually delimited by the leaf veins. The dark brown to almost black leaf spots give an almost charred appearance to the leaves, while on the lower surface the spots are grey becoming brown with age. GEOGRAPHICAL DISTRIBUTION: Africa: Ethiopia, Ghana, Guinea, Nigeria, Sierra Leone, Tanzania, Togo, Asia: Burma, India, North America: Canada (Ontario), West Indies (Barbados, Grenada, Jamaica, St. Vincent, Puerto Rico, Trinidad); South America: Venezuela. TRANSMISSION: Presumably by wind-borne and rain-splash dispersed conidia, surviving adverse periods in crop debris.

Plasmopara viticola. [Descriptions of Fungi and Bacteria].

1989 ◽  
Author(s):  
G. Hall
Keyword(s):  
Geographical Distribution ◽  
Secondary Infection ◽  
Plasmopara Viticola ◽  
Early Summer ◽  
Plant Diseases ◽  
Infected Leaf ◽  
Active Growth ◽  
Grape Vine ◽  
Distribution Maps ◽  
Leaf Tissues

Abstract A description is provided for Plasmopara viticola. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Ampelopsis brevipedunculata, A. hederacea, A. heterophylla, A. veitchii, Ampelocissus acetosa, A. latifolia, A. salmonea, Cissus caesia, C. gracilis, C. hypoglauca, C. polyantha, Cordifolia sempervirens, Cinerea sp., Parthenocissus quinquefolia, P. tricuspidata, Solonis robusta, Vitis aestivalis, V. amurensis, V. arizonica, V. berlandieri, V. californica, V. cinerea, V. coignetiae, V. cordifolia, V. girdiana, V. labrusca, V. lanata, V. monticola, V. pagnuccii, V. riparia, V. romaneti, V. rupestris, V. silvestris, V. treleasei, V. vinifera. DISEASE: Grape vine downy mildew; the fungus is an obligately biotrophic plant pathogen. All tissues bearing stomata are infected, becoming discolored, malformed and necrotic. Lesions on affected organs develop a white felt of sporangiophores. Leaves are most susceptible to attack during active growth in early summer, and when very mature in the autumn. Sporangiophores may appear directly on healthy green leaf tissues with no overlying lesion, or as a dense felt under yellow oily lesions on the upper surface (if humidity is high, 5-15 days after infection), or may be absent, leaves presenting only a mosaic of small, angular yellow or dark-red blemishes, limited by the secondary veins (mainly on old leaves in the autumn). During early growth, whole branches are attacked, but later only the extremities of branches are invaded. Infected shoots turn brown, curl up or become hooked at their tips. Nodes are more susceptible to attack than internodes. Tendrils, petioles, inflorescences and bunches also develop similar brown spots and lesions. Bunches are susceptible until the grapes are 5-6 mm diam., after which infection is rare (grey rot followed later by brown rot). Subsequent browning and desiccation of the bunch is caused by penetration of the bunch stalk by mycelium from earlier infections elsewhere. GEOGRAPHICAL DISTRIBUTION: See CMI Distribution Maps of Plant Diseases 221. TRANSMISSION: Oospores present in infected leaf tissues from the previous season's crop germinate in the spring, when air temperatures exceed 12°C and at least 10 mm rain falls in 24 hours, releasing zoospores into water or onto very moist soil from sporangia (64, 2458). Zoospores are projected onto vine leaves near the soil by rain splash, germinate to give hyphae and penetrate tissues via their stomata. Sporangia are liberated in moist air only, are disseminated by air currents, and remain viable for five days in dry air, producing secondary infection sites. Production of sporangia occurs at a relative humidity of 95-100%, and an air temperature of 13-27°C (optimum 18-22°C). Mycelium may overwinter between the bud scales and in diseased leaves, but it has not been established whether this contributes substantially to re-infection of healthy leaf tissues the following spring. There is no evidence for systemic transmission.

Pseudomonas tabaci. [Descriptions of Fungi and Bacteria].

1967 ◽  
Author(s):  
J. F. Bradbury
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Plant Material ◽  
Solanum Melongena ◽  
Datura Stramonium ◽  
Infected Leaf ◽  
Adjacent Tissue ◽  
Windy Weather ◽  
North And South America ◽  
North And South

Abstract A description is provided for Pseudomonas tabaci. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On at least 12 species of Nicotiana, as well as Capsicum annuum, Datura stramonium, Lycopersicon esculentum, Physalis grandiflora, Solanum melongena, S. nigrum and S. tuberosum (3: 611). Also infects plants belonging to numerous families, including some monocotyledons, when inoculated. The pathogen has been found naturally infecting various weeds (15: 613, 750), on the roots of weeds and crop plants without producing disease (21: 540) and associated with soyabean leaf pustule (29: 586: 35: 640). DISEASE: Wildfire of tobacco, a leaf spot. Chloroti spots appear and as they enlarge the centres become brown and dead and are surrounded by a wide chlorotic halo caused by the spread of a toxin into the adjacent tissue. Angular leaf spot, caused by P. angulata and does not produce the toxin shows no haloes. GEOGRAPHICAL DISTRIBUTION: Widespread in parts of Africa,. Asia, Europe, North and South America (CMI Map 293, 1954). Additional reports include those from Nyasaland (Malawi) (41: 7), Morocco (42: 631), U.S.S.R. (37: 738; 40: 51:), Belgium (34: 345), Greece (34: 108; 40: 649), Poland (41: 568). and Colombia (33: 82). TRANSMISSION: The pathogen can overwinter and be carried into new areas on seed, in soil and in unrotted plant material, particularly if dry (3: 105, 611, 612; 15: 179). It can also live saprophytically for long periods on the roots of various crops and weeds in the absence of tobacco (21: 540). The bacteria spread rapidly in water droplets in wet, windy weather (2: 345; 15: 537). Various other agents may spread the disease, particularly when plants are wet. The chewing of infected leaf by workers has also been suggested as a means of spread (3: 612).

Haplobasidion musae. [Descriptions of Fungi and Bacteria].

1976 ◽  
Author(s):  
M. B. Ellis
Keyword(s):  
Geographical Distribution ◽  
Leaf Spot ◽  
Leaf Surface ◽  
Lower Surface ◽  
Axis Parallel

Abstract A description is provided for Haplobasidion musae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On living leaves of Musa causing diamond-shaped, white, pale grey or brown spots each with dark purple to black border, spots often very pale on the upper surface, darker on the lower surface. DISEASE: Diamond (or Malayan) leaf spot of banana (Musa). Although the fungus was described only in 1957 the disease, as has been pointed out (51, 1688), was first reported by Knowles from Fiji in 1916. On the upper leaf surface the spots are greyish white with straight edges, diamond shaped with a black border, 4-5.5 × 3-4 mm, longer axis parallel to the veins, border 0.5 mm wide. These lesions may be surrounded by a watersoaked area often several times their size. GEOGRAPHICAL DISTRIBUTION: Fiji, Malaysia (W.) and Samoa (W.); (CMI Map 474, ed. 1, 1971). TRANSMISSION: No studies reported.

Cochliobolus pallescens. [Descriptions of Fungi and Bacteria].

1990 ◽  
Author(s):  
A. Sivanesan
Keyword(s):  
Hong Kong ◽  
Sierra Leone ◽  
Papua New Guinea ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Solomon Islands ◽  
Ear Rot ◽  
Black Point ◽  
Leaf Spots ◽  
Windward Islands

Abstract A description is provided for Cochliobolus pallescens. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Common on many graminicolous and non-graminicolous hosts. Important cereals and grasses include Eleusine, Hordeum, Oryza, Panicum, Paspalum, Pennisetum, Poa, Saccharum, Setaria, Sorghum, Triticum and Zea economically important dicot hosts include Allium (59, 4867), Arachis (53, 1647), Brassica (66, 3075), Canna, Calendula, Calotropis (44, 1832; 66, 3587), Carica (61, 5129), Cinnamomum, Citrus (68, 843), Coriandrum, Dahlia, Fagopyrum (64, 2425), Gaillardia, Hevea (56, 1257; 67, 5560), Musa (54, 4051), Solanum (50, 3484). DISEASE: Leaf spots of cereals, black point of wheat (44, 102), leaf spot and on stems of rubber (56, 1257; 67, 5560), ear rot of barley (62, 1005), rot of garlic (59, 4867). GEOGRAPHICAL DISTRIBUTION: Australia, Bangladesh, Brunei, Burma, Canada, Colombia, Cuba, Denmark, Egypt, Ethiopia, Fiji, Ghana, Guinea, Hong Kong, India, Indonesia, Iran, Jamaica, Japan, Kenya, Malaysia, Malawi, Nepal, Nigeria, Pakistan, Papua New Guinea, Peru, Philippines, Sierra Leone, Singapore, Solomon Islands, Somalia, Sri Lanka, Swaziland, Sudan, Taiwan, Tanzania, Thailand, Trinidad, USA, USSR, Venezuela, Windward Islands, Zambia, Zimbabwe. TRANSMISSION: By wind-borne conidia and seed-borne.

Pestalozziella subsessilis. [Descriptions of Fungi and Bacteria].

2012 ◽  
Author(s):  
T. V. Andrianova
Keyword(s):  
United Kingdom ◽  
Czech Republic ◽  
New Jersey ◽  
New Zealand ◽  
Geographical Distribution ◽  
Leaf Spot ◽  
Economic Impacts ◽  
Conservation Status ◽  
Infraspecific Variation ◽  
Chaetomella Raphigera

Abstract A description is provided for Pestalozziella subsessilis, a colonizer of living leaves, causing leaf spot symptoms leading to leaves fading and dying. Some information on its dispersal and transmission, economic impacts, infraspecific variation and conservation status is given, along with details of its geographical distribution (USA (Florida, Kansas, Louisiana, Mississippi, Missouri, New Jersey, Wisconsin), Kazakhstan, Russia, New Zealand, Austria, Bulgaria, Czech Republic, Germany, Hungary, Italy, Poland, Ukraine, and United Kingdom), hosts (Geranium carolinianum (leaf), G. collinum (leaf), G. columbianum (leaf), G. columbinum (leaf), G. macrorrhizum (leaf), G. maculatum (leaf), G. palustre (leaf), G. pratense (leaf), G. pusillum (leaf), G. pyrenaicum (leaf), G. robertianum (leaf), G. sanguineum (leaf), G. sylvaticum (leaf), G. wlassovianum (leaf), Geranium sp., and Oxypolis rigidor [Tiedemannia rigida]) and associated fungi Chaetomella raphigera.

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