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Recent taxonomic revisions have caused the bacteria ''Erwinia chrysanthemi'' to be renamed: ''Dickeya dadantii''.〔''Genome Evolution Laboratory.'' Genome Center of Wisconsin, 17 Jan. 2007. Web. 30 Oct. 2012. 〕 ''D. dadantii'' is a gram-negative bacillus that belongs to the family ''Enterobacteriaceae''. It is a close relative of ''E. coli'' and other animal pathogens that include ''Salmonella'', ''Shigella'', ''Klebsiella'', ''Proteus'' and ''Yersinia''. Members of this family are facultative anaerobes, able to ferment sugars to lactic acid, have nitrate reductase, but lack oxidases. Even though many clinical pathogens are part of the ''Enterobacteriaceae'' family, most members of this family are plant pathogens. ''D. dadantii'' is a motile, nonsporing, straight rod-shaped cell with rounded ends. Cells range in size from 0.8 to 3.2 μm by 0.5 to 0.8 μm and are surrounded by numerous flagella (peritrichous).〔 In the natural plant environment, ''D. dadantii'' causes plant maladies such as necrosis, blight and “soft rot,” which is a progressive tissue maceration. ''D. dadantii'' contains many pectinases that are able to macerate and break down the plant cell wall material. This exposed part of the plant releases nutrients that can facilitate bacterial growth. Commonly infected plants include potato tubers, bulbs of vegetables, and ornamental crops. ==Hosts== ''D. dadantii'' causes disease on several different ornamental and horticultural host plants throughout the world including: tropical, subtropical, and temperate climates. The host range of ''D. dadantii'' continues growing as new susceptible species are continuously being documented. It has also been found in soils,〔Robert-Baudouy J, Nasser W, Condemine G, Reverchon S, Shevchik VE, Hugouvieux-Cotte-Pattat N (2000) Pectic enzymes of ''Erwinia chrysanthemi'', regulation and role in pathogenesis. In: Stacey G, Keen NT (eds) Plant–microbe interactions, vol 5. APS, St. Paul, pp 221–268〕 rivers and irrigation water.〔Cother EJ, Gilbert RL (1990) Presence of ''Erwinia chrysanthemi'' in two major river systems and their alpine sources in Australia. Journal of Applied Bacteriology, Vol. 69:629–738〕 Host specificity is not yet fully understood. Originally pathovar groups were documented according to the hosts from which they were isolated. Today 50+ species have been identified and more are possible if another classification system based on biovars were to be used.〔Samson, R., and Nassan-Agha, N. 1978. Biovars and serovars among 129 strains of ''Erwinia chrysanthemi''. Pages 547-553 in: Proc. Int. Conf. Plant Pathog. Bact., 4th Station de Pathologie Vegetale et Phytobacteriologie, Angers, France. 1978. Ed. gibert-Clarey, Tours, France.〕 Disease is most often reported on bananas, carnations, and chrysanthemums, but the list of host species is quite vast. Important host families and species economically affected include: There are also many significant hosts for ''D. dadantii'' present in ornamental and floriculture industries, with the families including: Note: the plant families listed above show examples of some specific species infected within each family, not to say ''D. dadantii'' has the ability to infect every species within a family.〔EPPO Data sheets on quarantine pests: Erwinia chrysanthemi. In EPPO quarantine pest. Retrieved from http://www.eppo.int/QUARANTINE/bacteria/Erwinia_chrysanthemi/ERWICH_ds.pdf〕〔Barras F, Vangijsegem F, Chatterjee AK (1994) Extracellular enzymes and pathogenesis of soft-rot Erwinia. Annu Rev Phytopathol 32: 201–234.〕 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「Dickeya dadantii」の詳細全文を読む スポンサード リンク
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