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丁鱥溃疡病的病原菌分离、鉴定与人工感染试验 总被引：3，自引：0，他引：3
采用细菌常规分离方法分离丁鱥溃疡病病原，并对所获得的纯培养物进行VITEK-32鉴定和人工感染试验，结果显示：维罗纳气单胞菌温和其变种是丁鱥溃疡病的主要病原菌。 相似文献
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由丁香假单胞菌猕猴桃致病变种Pseudomonas syringae pv. actinidiae (Psa)侵染引起的猕猴桃细菌性溃疡病(kiwifruit bacterial canker)是全球猕猴桃生产上最具毁灭性的细菌病害。为探明福建、安徽、四川和陕西4省Psa菌株的生物型和遗传多样性,用5对PCR特异性引物PsaJ-F/-R、PsaK-F/-R、Tac-F/-R、Con002-F/-R和avrRps4-F1/-R2检测Psa菌株的生物型;用4对PCR引物27F/1492R、PsaF1/PsaR2、gapA-Fps/Rps和rpoD+364s/-1222ps分别扩增16S rRNA、ITS、gapA和rpoD基因,进行多基因联合分析Psa菌株的遗传多样性。结果表明,特异性引物Tac-F/-R从47株Psa菌株中均能扩增出一条545 bp的特异条带,其他4对引物未扩增出任何条带,说明供试Psa菌株的生物型均为biovar 3。多基因联合分析表明,4省Psa存在丰富的遗传多样性,4个群体共检测出27个单倍型,单倍型多样性为0.955。安徽、福建、四川和陕西群体的单倍型数差异较大,分别为1、8、12个和12个。4个群体的多态性位点数、核苷酸多样性和平均核苷酸差异数差异极显著(P<0.01),其中福建群体的多态性最丰富,而安徽群体的多态性最低。AMOVA分析表明,3.6%的遗传变异来源于种群间,而96.4%的遗传变异来源于种群内,说明种群内变异是遗传变异的主要来源。遗传分化分析表明,安徽省Psa群体与其他3个群体间的遗传分化极高(Fst>0.175),福建、四川和陕西群体间的遗传分化水平较低(Fst<0.017)。研究结果有利于了解福建省Psa的来源,为阻断Psa的传播和猕猴桃细菌性溃疡病的长期可持续控制提供了理论参考。 相似文献
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Phylotype and sequevar variability of Ralstonia solanacearum in Brazil,an ancient centre of diversity of the pathogen 
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下载免费PDF全文 The β‐proteobacterium Ralstonia solanacearum causes bacterial wilt of many plant species. Knowledge of phylotype and sequevar variability in populations of this microorganism is useful for implementing control measures, particularly host resistance. To this end, 301 isolates of R. solanacearum were collected from different geographic regions and hosts in Brazil. Their phylotype and sequevar characterization was used to determine the amount and distribution of phenetic and phylogenetic variability. Isolates were classified into phylotypes I (n = 48), clade 1; and phylotype II, clades 2–5. Phylotype II was divided into subclusters IIA (n = 112) and IIB (n = 141). Phylotype II was widely distributed, whereas phylotype I isolates were found in Central, Northern, and Northeastern regions of Brazil. There were 108 haplotypes identified among endoglucanase (egl) gene sequences from 301 isolates and 32 haplotypes among DNA repair (mutS) gene regions from 176 isolates. The egl and mutS sequence analyses identified eight known (1, 4, 7, 18, 27, 28, 41 and 50) and four new (54, 55, 56 and 57) sequevars. Phylotype IIB showed high diversity in sequevars and host range. Multiplex PCR, using primers specific to the Moko ecotype, characterized banana and long pepper isolates as sequevar 4 and 4/NPB, respectively. This constitutes the first report of the emergent ecotype IIB/4NPB in a new host, long pepper. The majority of sequevars were associated with geographic regions. This high variability of R. solanacearum in Brazil suggests use of host resistance to control bacterial wilt should be mainly focused by region. 相似文献
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