Duarte V, de Boer S H, Ward L J, de Oliveira A M R
Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
J Appl Microbiol. 2004;96(3):535-45. doi: 10.1111/j.1365-2672.2004.02173.x.
To determine the characteristics of bacteria associated with the blackleg disease of potato in Brazil and compare them with species and subspecies of pectolytic Erwinia.
Biochemical and physiological characteristics of 16 strains from blackleg-infected potatoes in State of Rio Grande do Sul, Brazil, were determined and differentiated them from all the E. carotovora subspecies and E. chrysanthemi. Pathogenicity and maceration ability of the Brazilian strains were greater than those of E. carotovora subsp. atroseptica, the causal agent of potato blackleg in temperate zones. Analyses of serological reaction and fatty acid composition confirmed that the Brazilian strains differed from E. carotovora subsp. atroseptica, but the sequence of 16S rDNA gene and the 16S-23S intergenic spacer (IGS) region confirmed the Brazilian strains as pectolytic Erwinia. Restriction analysis of the IGS region differentiated the Brazilian strains from the subspecies of E. carotovora and from E. chrysanthemi. A unique SexAI restriction site in the IGS region was used as the basis for a primer to specifically amplify DNA from the Brazilian potato blackleg bacterium in PCR.
The bacterium that causes the blackleg disease of potato in Brazil differs from E. carotovora subsp. atroseptica, the blackleg pathogen in temperate zones. It also differs from other subspecies of E. carotovora and from E. chrysanthemi and warrants status as a new subspecies, which would be appropriately named E. carotovora subsp. brasiliensis.
The blackleg disease of potato is caused by a different strain of pectolytic Erwinia in Brazil than in temperate potato-growing regions. The Brazilian strain is more virulent than E. carotovora subsp. atroseptica, the usual causal agent of potato blackleg.
确定巴西马铃薯黑胫病相关细菌的特征，并将其与果胶分解欧文氏菌的种和亚种进行比较。
测定了巴西南里奥格兰德州黑胫病感染马铃薯的16个菌株的生化和生理特征，并将它们与所有胡萝卜软腐欧文氏菌亚种和菊欧文氏菌区分开来。巴西菌株的致病性和浸解能力高于温带地区马铃薯黑胫病的病原菌胡萝卜软腐欧文氏菌亚种atroseptica。血清学反应和脂肪酸组成分析证实，巴西菌株与胡萝卜软腐欧文氏菌亚种atroseptica不同，但16S rDNA基因序列和16S - 23S基因间隔区（IGS）证实巴西菌株为果胶分解欧文氏菌。IGS区域的限制性分析将巴西菌株与胡萝卜软腐欧文氏菌亚种及菊欧文氏菌区分开来。IGS区域中一个独特的SexAI限制性位点被用作引物的基础，以在PCR中特异性扩增来自巴西马铃薯黑胫病菌的DNA。
引起巴西马铃薯黑胫病的细菌与温带地区的黑胫病病原菌胡萝卜软腐欧文氏菌亚种atroseptica不同。它也与胡萝卜软腐欧文氏菌的其他亚种以及菊欧文氏菌不同，有资格成为一个新亚种，应命名为胡萝卜软腐欧文氏菌亚种brasiliensis。
巴西马铃薯黑胫病是由一种与温带马铃薯种植区不同的果胶分解欧文氏菌菌株引起的。巴西菌株比马铃薯黑胫病通常的病原菌胡萝卜软腐欧文氏菌亚种atroseptica毒性更强。
