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Fusarium wilt is a common vascular wilt fungal disease, exhibiting symptoms similar to Verticillium wilt. The pathogen that causes Fusarium wilt is ''Fusarium oxysporum'' (''F. oxysporum'').〔Snyder, W.C. and Hansen, H.N. 1940. The species concept in Fusarium. Amer. J. Bot. 27:64-67.〕 The species is further divided into forma specialis based on host plant. == Hosts and symptoms == The fungal pathogen ''Fusarium oxysporum'' affects a wide variety of hosts of any age. Tomato, tobacco, legumes, cucurbits, sweet potatoes and banana are a few of the most susceptible plants, but it will also infect other herbaceous plants.〔("Fusarium Wilt." ) Pan Germany. Pestizid Aktions-Netzwerk. Web. 23 Nov. 2010.〕 ''Fusarium oxysporum'' generally produces symptoms such as wilting, chlorosis, necrosis, premature leaf drop, browning of the vascular system, stunting, and damping-off. The most important of these is vascular wilt.〔Agrios, 1988; Smith et al., 1988〕 Fusarium wilt starts out looking like vein clearing on the younger leaves and drooping of the older lower leaves, followed by stunting of the plant, yellowing of the lower leaves, defoliation, marginal necrosis and death of the plant. On older plants, symptoms are more distinct between the blossoming and fruit maturation stages.〔(''Fusarium oxysporum''. ) Andre K. Gonsalves and Stephen A. Ferreira. Department of Plant Pathology, CTAHR; University of Hawaii at Manoa.〕 ''Fusarium oxysporum'' is split into divisions called ''formae speciales'' (singular ''forma specialis'', abbreviated ''f.sp.''). There are over 100 formae speciales divisions,〔Gerlach, Wolfgang. Nirenberg, Helgard. Genus Fusarium: A Pictorial Atlas. Berlin-Dahlem. 1982〕 each with one or two different races. Each forma specialis within the species are host-specific (i.e. specific to a certain plant) and produce different symptoms: ''F. oxysporum'' f. sp. ''batatas'' affects sweet potato. The symptoms include leaf chlorosis, stunting, and leaf drop. It is transmitted through the soil and through vascular wounds in plant material. ''F. oxysporum'' f. sp. ''cubense'' causes Panama disease on banana. It is found everywhere bananas are grown in Africa, Asia, Central and South America. It attacks banana plants of all ages and spreads mainly through the soil. It causes wilting and yellowing of the leaves.〔Booth, C. 1971. The Genus Fusarium. Commonwealth Agricultural Bureaux. 139.〕 ''F. oxysporum'' f. sp. ''lycopersici'' causes vascular wilt in tomato. The disease starts out as yellowing and drooping on one side of the plant. Leaf wilting, plant stunting, browning of the vascular system, leaf death, and lack of fruit production also occur.〔(''Fusarium oxysporum'' f. sp. ''lycopersici'' (Sacc.) W.C. Snyder and H.N. Hans. ) Prepared by Mui-Yun Wong. PP728 Soilborne Plant Pathogen Class Project, Spring 2003.〕 ''F. oxysporum'' f. sp. ''melonis'' attacks muskmelon and cantaloupe. It causes damping-off in seedlings and causes chlorosis, stuting and wilting in old plants. Necrotic streaks can appear on the stems. 〔Booth, C. 1971. The Genus Fusarium. Commonwealth Agricultural Bureaux. 146.〕 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「Fusarium wilt」の詳細全文を読む スポンサード リンク
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