Phytophthora porri. [Descriptions of Fungi and Bacteria].

Author(s):  
D. Jean Stamps

Abstract A description is provided for Phytophthora porri. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Allium spp. (leek, onion, scallion), cabbage, Campanulapersicifolia, tulip. DISEASE: White tip of leek; onion white leaf spot; storage rot of white cabbage; crown rot of Campanula. GEOGRAPHICAL DISTRIBUTION: Europe (UK, Netherlands, Switzerland, Norway); Asia (Japan). (CMI Map 204, ed. 2, 1967). TRANSMISSION: Suggested by wind-blown sporangia from the soil surface to leek leaves (11, 151). Sporangia were found in soil round diseased Campanula plants (31, 65). Tulip bulbs were invaded through the young bud but not through the scale leaf (54, 2855). Cut stems of cabbages were infected from the soil at harvest by soil splash or from the cutting knife (52, 266; 56, 899).

Author(s):  
E. Punithalingam

Abstract A description is provided for Phoma sorghina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Gramineae and all kinds of plants. Also isolated from soil, air and various animal sources. DISEASE: A minor leaf spot of cereals and grasses. The visible symptoms vary considerably; on sorghum leaves spots are usually irregular or rounded, yellowish-brown or grey with definite reddish-purple margins or indefinite in outline, reaching 1 cm or more in width. Pycnidia develop within spots on leaves, glumes and seeds. Also the fungus has been implicated with pre- and post-emergence death of seedlings of Macroptilium and Sylosanthes species (54, 1779) crown rot of bananas (61, 3556), leaf spot of Agave americana and stem rot of Euphorbia tirucalli (63, 3383), brown stem canker of Leucosperum cordifolium (56, 253). GEOGRAPHICAL DISTRIBUTION: A ubiquitous fungus occurring in tropical and subtropical regions. Africa (Botswana, Cameroon, Egypt, Ethiopia, Gambia, Kenya, Malawi, Mauritius, Mozambique, Nigeria, Senegal, Sierra Leone, South Africa, Sudan, Tanzania, Togo, Uganda, Zaire, Zambia, Zimbabwe); Asia (Bangladesh, Brunei, Burma, China, Hong Kong, India, Indonesia (Irian Jaya), Laos, Malaysia, Nepal, Pakistan, Saudi Arabia, Sri Lanka, Taiwan, USSR); Australasia and Oceania (Australia, Hawaii, New Zealand, Papua New Guinea, Solomon Islands); Europe (Germany, Portugal, Italy, UK); North America (Canada, USA); Central America and West Indies (Antigua, Guatemala, Honduras, Jamaica, Nicaragua, Puerto Rico, Trinidad); South America (Argentina, Bolivia, Brazil, Colombia). TRANSMISSION: Probably by contaminated seed; the fungus has been found on or isolated from several seed samples (1, 289; 33, 599; 47, 2153; 54, 1779; 60, 367; 61, 4102). In Taiwan P. sorghina has been found to be transmitted from seed to seedlings (62, 4281). The fungus has also been claimed to persist on trash and weed hosts and remain viable up to 1 yr but lose its viability after 2 yr storage on dry infected leaves (Koch & Rumbold, 1921).


Author(s):  
E. Punithalingam

Abstract A description is provided for Septoria cannabis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOST: Cannabis sativa (hemp). DISEASE: White leaf spot or leaf blight of hemp. Symptoms usually appear on basal leaves as round or ellipsoidal to polygonal, whitish or ochraceous yellow lesions with a conspicuous dark brown border. Affected leaves become curled and withered up towards the edges and fall prematurely leaving much of the lower part of the stem defoliated (15, 97, 805). GEOGRAPHICAL DISTRIBUTION: Asia, Europe and North America (CMI Map No. 477, ed. 1, 1971). New records not mapped are: Asia (Kashmir, Pakistan). TRANSMISSION: Detailed studies have not been reported but conidia are presumed to be disseminated by rain-splash and wind blown water. The fungus could also be carried over in crop residues.


Author(s):  
D. Jean Stamps

Abstract A description is provided for Phytophthora cryptogea. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On a wide range of glasshouse and field crops. Tomato, ornamentals (including petunia, aster, chrysanthemum, Tagetes, tulip, wallflower, Gerbera, gloxinia, Matthiola, Papaver, cineraria, dahlia, Gypsophila, Hebe, Rhododendron, Osteospermum, zinnia), potato, chicory, spinach, bean, onion, cucurbits, eggplant, hop, sunflower, safflower, lucerne, Cupressus, Chamaecyparis, chestnut and others. DISEASE: Damping-off and foot rot of tomato; foot rots of aster, Matthiola and Gerbera; black neck of chrysanthemum; tulip shanking; corm, stem and leaf rot of gloxinia; crown rot of Iceland poppy; pink rot of potato; sunflower stem rot; chestnut wilt; damping-off, root rots and wilts of many other hosts. GEOGRAPHICAL DISTRIBUTION: Europe (UK, Irish Republic, Austria, Czechoslovakia, Denmark, France, Germany, Greece, Italy, Netherlands); Africa (Egypt, Rhodesia); Asia (Iran); Australia; New Zealand; N. America (Canada, USA). (CMI Map 99, ed. 4, 1976). TRANSMISSION: Soil-borne, persisting for several years (6, 669). Tulip bulbs were invaded from the soil (18, 183). Movement of zoospores was studied (56, 1029). Isolates were obtained from glasshouse water supplies (1, 94). There was a high frequency of recovery on baiting irrigation water in Victoria (57, 2174).


Author(s):  
B. C. Sutton

Abstract A description is provided for Mycocentrospora acerina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: A very wide host range (29, 364); parsley, celery, carrot and parsnip are among the most important economically. DISEASE: Pansy leaf spot; celery storage rot; root rot, canker and black crown rot of parsnip; liquorice rot of carrot. GEOGRAPHICAL DISTRIBUTION: Europe (UK, Ireland, Germany, Czechoslovakia, Netherlands, Poland, Rumania, USSR, Denmark); N. America (USA, Canada); Australia, New Zealand. TRANSMISSION By splash dispersed conidia; these are viable for short periods only (26, 133). Survival for longer periods is by infected debris and chlamydospores in the soil (23, 324; 45, 681; 52, 899). Water-borne spread is possible (49, 1526) and transmission on pansy seeds has been demonstrated (51, 422).


Author(s):  
E. Punithalingam

Abstract A description is provided for Septoria carthami. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Carthamus tinctorius and C. mareoticus. DISEASE: White leaf spot of safflower. Early symptoms appear as small distinct brownish lesions which enlarge and become circular or irregular and up to 6 mm wide. As the disease progresses lesions sometimes coalesce to form large blotches. Older lesions are usually bordered by dark brick margins with ash grey centres. GEOGRAPHICAL DISTRIBUTION: Africa (Egypt); Asia (Iraq, Turkey, USSR, West Siberia); Europe (Bulgaria, Rumania); North America (USA, Indiana, Texas). TRANSMISSION: It has been claimed that the fungus was introduced into West Siberia with infected seeds (14, 493-494). Also the fungus is probably disseminated by water-splash or by mechanical means.


Author(s):  
A. Sivanesan

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.


Author(s):  
T. V. Andrianova

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.


Author(s):  
E. Punithalingam

Abstract A description is provided for Ascochyta desmazieresii. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Lolium multiflorum and L. perenne. DISEASE: Glume and leaf spot of Italian and perennial ryegrasses. At first leaf lesions start as small purplish or chocolate-brown spots with a distinct red-purple margin. With time these enlarge, become irregular or elliptical, up to 5 mm long and distinctly visible on both sides of the leaves. Finally the centres of older lesions fade to fawn to straw yellow with numerous pycnidia immersed within the leaf tissue on both sides of the leaves but usually abundant pycnidia occur on the lower side. GEOGRAPHICAL DISTRIBUTION: Asia (Japan); Europe (Belgium, Czechoslovakia, Denmark, France, Irish Republic, UK); N. America (USA, California, Oregon, Washington); S. America (Chile, Brazil). TRANSMISSION: No specific studies reported; infection is presumably spread by air-borne conidia in wet weather or heavy dews. The fungus is also probably carried over on crop residues and debris in soil.


Author(s):  
J. E. M. Mordue

Abstract A description is provided for Pestalotiopsis mangiferae. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Mangifera indica; also on Anacardium occidentale, Combretum decandrum, Eucalyptus spp., Mimusops spp., Vitis vinifera and many other unrelated host plants. DISEASE: Grey leaf spot of Mangifera indica. The spots vary in size from a few mm to several cm in length, are usually sharply delimited by a dark, raised border, and are silvery grey above and grey to brown below; leaf spots on other hosts are similar. Brown spot or rot of mango fruits is also known. GEOGRAPHICAL DISTRIBUTION: Ghana, Nigeria, Sierra Leone, Tanzania, Uganda, Zaire, Zambia; Bangladesh, Brunei, Burma, Hong Kong, India, Malaysia, Nepal, Sabah, Solomon Islands, Sri Lanka; Australia; Dominican Republic; Venezuela. TRANSMISSION: Inoculation studies with conidia and mycelium have shown P. mangiferae to be a weak parasite, capable of infecting young injured leaves, injured fruits, older uninjured leaves and healthy fruits if in contact with diseased tissue (35, 378; 40, 421). It has been isolated from soil, but the possibility of transmission through soil has not been investigated.


Author(s):  
J. F. Bradbury

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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