Venturia inaequalis. [Descriptions of Fungi and Bacteria].

Author(s):  
A. Sivanesan

Abstract A description is provided for Venturia inaequalis. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Principally on apple (Malus pumila), and other species of Malus. Also recorded on Pyrus spp., Sorbus spp. Pyracantha, Cotoneaster integerrima, Crataegus oxyacantha, Viburnum, Sarcocephalus esculentus (36, 278) (Herb. IMI). DISEASE: Causes scab or black spot of apple, a common disease which can produce serious losses in both quantity and quality of fruit. The fungus can infect shoots, buds, blossoms, leaves and fruit. Symptoms appear initially as small, dull, pale spots particularly on the underside of leaves in spring. These enlarge as a mass of radiating subcuticular hyphae develops, forming dark circular lesions visible on both leaf surfaces; a slight puckering or blistering effect may also occur. Older lesions turn grey as the infected host tissue is killed. Scab on fruit is usually more conspicuous than on leaves, but varies according to resistance, pathogen virulence etc. Severe lesions may involve most of the fruit and become suberized and cracked, thus allowing entrance of secondam rotting organisms. Early infection of young fruit may cause shedding or distorted growth. On older fruit smaller secondary, lesions (pepper spot) often develop around a large primary scab. Infection of mature fruit may become visible during storage as sunken, black lesions. Lesions on young shoots appear as light brown blister-like swellings. GEOGRAPHICAL DISTRIBUTION: Worldwide wherever apples are grown (CMI Map 120, ed. 3, 1966). TRANSMISSION: The fungus overwinters primarily on leaf litter where the saprophytic sexual (perithecial) stage occurs. In wet spring weather the resulting perithecia release masses of airborne ascospores which infect the susceptible young foliage (42, 204). Dormant overwintering lesions on shoots and bud scales may also occur; these produce conidia which can infect young spring growth. Primary (spring) lesions produce conidia which cause secondary infection of foliage, fruit and shoots during wet summer weather. Conidia are dispersed chiefly by rain splash but may be present in the air near heavily infected trees during dry conditions (40, 757).

Author(s):  
A. Sivanesan

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).


Author(s):  
C. Booth

Abstract A description is provided for Nectria radicicola. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On a very wide range of hosts, Gymnospermae, Monocotyledonae and Dicotyledonae, particularly in temperate regions, especially Fragaria vesca, Narcissus, Vitis vinifera. DISEASE: Root rot, dry brown rot, storage rot or dry rot (37: 3); wilt (32: 261); root plate rot of Narcissus (30: 160); black rot of strawberry (28: 180); black spot of grapes (36: 449). GEOGRAPHICAL DISTRIBUTION: Widespread in Europe. Occurs in N. America, East and South Africa, Australia, New Zealand. TRANSMISSION: By water, rain splash or in soil; infection generally from soil. Contaminated soil is the principal source of infection in nurseries where the fungus is capable of existing for long periods as a saprophyte or as thick-walled chlamydospores (35: 769). Taylor (36: 449) found the fungus only penetrating grapes when the skin was broken.


Author(s):  
A. Sivanesan

Abstract A description is provided for Elsinoe ampelina. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Vitis spp., especially varieties of the European grape (V. vinifera) and of some North American grapes including V. rupestris, V. Iabrusca and V. aestivalis. Also on Vitis hybrids, especially those derived from susceptible Vinifera or Rupestris parents (27, 461, Arnaud & Arnaud). For details of susceptibility of cultivated varieties and hybrids see Gaudineau (general review), Arnaud & Arnaud, Jennings (33, 67), Boehm (39, 70), du Plessis, Goyal et al. (51, 2735), Krarajnan et al. (49, 2948), Mirica et al. (50, 2404). For susceptibility of tropical and North American Vitis spp. see Fennell (27, 461). DISEASE: Grape anthracnose, black spot of vine (spot anthracnose etc.), birds eye rot (fruits). General symptoms may include: leaves - curling downwards, laceration or chlorosis of leaf parts and death of entire young leaf; shot-hole and premature leaf abscission; stems - stunting and death of young shoots, deterioration of older shoots and stocks, loss of fruit yield; fruits - loss of young bunches and distortion, splitting, mummification or abscission of berries by direct attack on fruit surface. GEOGRAPHICAL DISTRIBUTION: Widespread in most grape-growing areas where suitable rainfall conditions occur (CMI Map 234, ed. 2, 1967). TRANSMISSION: Initially by splash dispersal of conidia produced from overwintered sclerotia on lesions on stems, petioles or old bunch stalks (du Plessis). Secondary infection from diseased leaves, fruits, etc.


Author(s):  
D. L. Hawksworth

Abstract A description is provided for Acremonium zonatum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: Known from leaves of Amaranthus gangeticus, Annona squamosa, Boehmeria nivea, Brillantaisia nitens, Calopogonium mucunoides, Coffea arabica, C. liberica-excelsa, C. robusta, Colocasia esculenta, Coridia dentata, Crotalaria anagyroides, Cucumis sativus, Eichhornia crassipes, Eranthemum nervosum, Erythrina senegalensis, Ficus carcia (var. celeste), Hypoestes verticillaris, Kosteletzkya grantii, Lindackeria bahobensis, Litchi chinensis, Momordica foetida, Morus acidosa, Musa sapientum, Pachira insignia (syn. Bombax sessile), Phaseolus atropurpureus, Plumeria alba, Solanum verbascifolium, Steriospermum bantharum and Vigna sinensis. DISEASE: Causal agent of 'fig zonate spot' and 'zonal leaf spot' of coffee but forming similar zonate leaf spots on a wide range of phanerogams (see above). GEOGRAPHICAL DISTRIBUTION: Widespread in tropical countries and known from Africa (Ghana, Guinea, Nigeria, Sierra Leone, Sudan, Tanzania, Zaire), Asia (Bangladesh, Brunei, India, Malaysia (Sabah, Sarawak), New Guinea, Taiwan, Western Samoa), West Indies (Jamaica, Puerto Rico, Windward Islands), Central America (Costa Rica), North America (USA, southern Louisiana), and South America (Peru, Venezuela). TRANSMISSION: Presumably mainly by rain splash but insects crawling over infected leaves could play some part. Old diseased foliage on the ground is probably the primary source of infection (28, 180). Inoculations by spraying spore suspensions and placing cultures on lower leaf surfaces successful (Tims & Olive, 1948).


Author(s):  
A. C. Hayward

Abstract A description is provided for Corynebacterium flaccumfaciens. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Phaseolus vulgaris and other Phaseolus spp., and on Glycine max, Zea mays and other hosts on inoculation (17: 810; Elliott, 31: 105, p. 20). DISEASE: Bacterial wilt. The pathogen is primarily a vascular parasite and spotting of the leaves and stems does not develop. GEOGRAPHICAL DISTRIBUTION: Restricted to parts of Australia, Europe and North America (CMI Map 370. Ed. 2, 1964). Reports by Hedges (5: 463; 18: 49), reproduced by Elliott (31: 105), of occurrence in Canada, Belgium, France and Germany have not been substantiated, and the last-named is specifically refuted by Stapp (40: 554). TRANSMISSION: Primarily on seed which may be infected externally, or internally as the result of systemic infection. The bacterium can remain viable and virulent for long periods (up to 24 years) in seed stored under laboratory conditions (25: 89). In the field, survival in soil for at least two winters between bean crops rotated with beet is recorded (37: 195). Corynebacterium flaccumfaciens does not spread by rain splash in the field as readily as other bacterial pathogens of the bean because of the more limited external development of the disease. Irrigation water may assist in localized spread (34: 339; 38: 641). Secondary infection is through wounds: the incidence of wilt has been increased by wounding below soil level and by wounding stem and leaf tissues (35: 503; 37: 195). Under certain conditions the nematode Meloidogyne incognita may provide wounds for entry of the pathogen (38: 641). The incidence of infection is also affected by soil type, being high in a sandy loam and low in a clay loam.


Author(s):  
B. J. Dyko

Abstract A description is provided for Colletotrichum acutatum. Information is included on the disease caused by the organism, its transmission, geographical distribution, and hosts. HOSTS: On Delphinium, Apium graveolens var. duka, Carica papaya, Parmentiera edulis, Persia americana, Fragaria, Capsicum frutescens, Juglans regia, Lycopersicon esculentum, Malus sylvestris, Solanum melongena, Flindersia brayleyana, Pinus elliottii (46, 370), Pinus radiata (49, 1806), Coffea arabica (50, 1241), Zinnia elegans, Z. haugeans (55, 3620); Magnolia fraseri*, Anemone*, Ranunculus*, Salvinia molesta*, (*herb. IMI). DISEASE: Black spot of strawberry, terminal crook disease of pine. GEOGRAPHICAL DISTRIBUTION: Africa (Kenya, Tanzania*); Asia (Sri Lanka*); Australasia (Australia, New Zealand); N. America (USA, North Carolina*), (*herb. IMI). TRANSMISSION: Rain splash and wind (54, 2357).


2020 ◽  
Vol 16 (6) ◽  
pp. 860-865
Author(s):  
Sedigheh Tavakoli-Dastjerdi ◽  
Mandana Tavakkoli-Kakhki ◽  
Ali R. Derakhshan ◽  
Azam Teimouri ◽  
Malihe Motavasselian

Background: Anal fissure (AF) is a common disease associated with severe pain and reduced quality of life. Factors related to lifestyle, including diet and bowel habits, play a pivotal role in its pathogenesis. Most of the chronic fissures are not responsive to drugs and more likely to recur. Given the significance of diet in Persian medicine (PM), investigation on physiopathology and appropriate foods can be useful for decreases in AF symptoms and consequences. Objective: This study was intended to evaluate the role of diet in the formation and progression of AF from the perspective of PM. Methods: In this study, the most important resources of PM dating back to thousands of years were reviewed. All these textbooks contained a section on AF, its causes, and treatment. Further analysis was performed on these resources in comparison with databank and resources of modern medicine to develop a food-based strategy for AF management. Results: From the view of PM, the warmth and dryness of anus temperament accounted for AF. Both Persian and modern medicine identified constipation as another cause for AF. Therefore, avoidance from some foods and commercial baked goods was recommended. Both Persian and modern medicine forbad the following foods: potato, cabbage, cauliflower, pasta, beef, fish, and so forth. High fiber and oligo-antigen diets with some limitations have garnered more attention. Conclusion: An integrative approach is recommended employing both Persian and modern medicine for AF. There have been some evidence in this regard, however standardized clinical trials are required for future research.


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.


Author(s):  
E. Punithalingam

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).


Author(s):  
C. Booth

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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