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Verticillium Wilt is a wilt disease of over 350 species of eudicot plants caused by six species of Verticillium genus, ''V. dahliae'', ''V. albo-atrum'', ''V. longisporum'', V. nubilum, V. theobromae and V. tricorpus. (See, for example, Barbara, D.J. & Clewes, E. (2003). "Plant pathogenic Verticillium species: how many of them are there?" Molecular Plant Pathology 4(4).297-305. Blackwell Publishing.)Many economically important plants are susceptible including cotton, tomatoes, potatoes, oilseed rape, eggplants, peppers and ornamentals, as well as others in natural vegetation communities. Many eudicot species and cultivars are resistant to the disease and all monocots, gymnosperms and ferns are immune. Symptoms are superficially similar to ''Fusarium'' wilts. There is no chemical control for the disease but crop rotation, the use of resistant varieties and deep plowing, may be useful in reducing the spread and impact of the disease. ==Hosts and symptoms== ''Verticillium'' spp. attack a very large host range including more than 350 species of vegetables, fruit trees, flowers, field crops, and shade or forest trees. Most vegetable species have some susceptibility, so it has a very wide host range.〔 A list of known hosts is at the bottom of this page. The symptoms are similar to most wilts with a few specifics to ''Verticillium''. Wilt itself is the most common symptom, with wilting of the stem and leaves occurring due to the blockage of the xylem vascular tissues and therefore reduced water and nutrient flow. In small plants and seedlings, ''Verticillium'' can quickly kill the plant while in larger, more developed plants the severity can vary. Some times only one side of the plant will appear infected because once in the vascular tissues, the disease migrates mostly upward and not as much radially in the stem.〔 Other symptoms include stunting, chlorosis or yellowing of the leaves, necrosis or tissue death, and defoliation. Internal vascular tissue discoloration might be visible when the stem is cut.〔 In ''Verticillium'', the symptoms and effects will often only be on the lower or outer parts of plants or will be localized to only a few branches of a tree. In older plants, the infection can cause death, but often, especially with trees, the plant will be able to recover, or at least continue living with the infection. The severity of the infection plays a large role in how severe the symptoms are and how quickly they develop.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Verticillium wilt」の詳細全文を読む スポンサード リンク
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