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1.
M. C. C. de Arruda † R. N. G. Miller M. A. S. V. Ferreira M. S. S. Felipe 《Plant pathology》2003,52(2):236-244
Fifty isolates of Crinipellis perniciosa originating from Theobroma cacao , Heteropterys acutifolia and Solanum lycocarpum , from six states within Brazil, were characterized through ERIC-PCR, representing the first application of this method for molecular characterization within C. perniciosa . Phenetic analysis of banding patterns revealed a separation of isolates on the basis of host of origin, with T. cacao -derived isolates showing only a 0·2 similarity level to a cluster comprising the isolates from H. acutifolia and S. lycocarpum . Considerable intraspecific variability was observed within C. perniciosa isolates from T. cacao , with distinct groups observed correlating with geographical origin. Given that a number of isolates from T. cacao from the Amazon region grouped with isolates from Bahia state, this work discusses the possibility that current C. perniciosa populations pathogenic on T. cacao in Bahia originated from the Amazon region, rather than from alternative host plants. 相似文献
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构建稻瘟病菌有性后代随机群体是研究目的基因遗传特点，乃至克隆目的基因的重要基础，但是在建立有性后代随机群体时，可能会有无性后代污染。采用先分离单个子囊，待其长成菌落并产生分生孢子后，再分离单个萌发的分生孢子的方法构建稻瘟病菌有性后代随机群体。利用基于重复DNA序列Pot2的rep-PCR方法对分离得到的有性后代进行DNA指纹分析，并评价构建的稻瘟病菌有性后代群体的质量。结果表明，构建的有性后代随机群体共包含176个后代。每个后代个体的DNA指纹图谱均与两亲本的DNA指纹图谱不一致；有性后代之间的DNA指纹图谱也彼此不一样，说明得到的有性后代个体都是由子囊孢子萌发形成的，且分离自不同的子囊。GUY11的rep-PCR扩增片段中的5个特异性片段的分离比例也都符合1:1的期望值，是按单个位点标记分离的，与已知的结果相吻合，说明有性后代随机群体的质量较高，不存在偏离现象，是一个较为理想的群体。同时，研究结果还得出基于Pot2的rep-PCR方法可以用来快速评价稻瘟病菌有性后代群体的质量。 相似文献
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采用ERIC-PCR、BOX-PCR和ITS技术，对江苏省6个市的24个小麦苗枯病菌（Clavibacter fangii）进行遗传多样性分析，并与其他10种病原细菌进行比较。结果表明，在相似率达60％时，ITS将24个小麦苗枯病菌分成了5簇。以相似性60％为界，ERIC-PCR将34个参试菌株分为14簇，而BOX．PCR只得到9簇，暗示这两种短重复序列在基因组中的分布不同；将两者电泳图谱结合，得到介于上述两者问的结果，所有菌株被分成12簇，24个小麦苗枯病菌分布在5簇中。3种分析方法相互验证，均说明江苏省小麦苗枯病菌基因组存在显著多样性。ERIC-PCR和BOX-PCR聚类证明了小麦苗枯病菌与棒形杆菌属（Clavibacter）亲缘关系较近，与其他属细菌亲缘关系较远。ERIC-PCR和BOX-PCR扩增基因组DNA指纹比ITS图谱具有更强的多样性。 相似文献
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用rep-PCR方法分析了病圃和大田的稻瘟菌的遗传谱系组成,并在CO39NILs6个近等基因系品种上进行毒性类型分析。结果表明,不同群体之间的遗传谱系和毒性类型均不完全相同,福建稻瘟菌群体在年度间存在明显的优势谱系,1999、2000年的优势谱系均为CFL03,2001年为CFL07;两个季节中的谱系类型组成差异小,早季病圃和大田及晚季大田优势谱系均为CFL07。年度间病圃与大田的毒性类型组成和优势类型都有很大的变化,1999年病圃的优势毒性类型为I20.1,而2000年则为I24.1和I34.1两个类型;毒性类型I1.1、I5.1、I11.1、I26.1和I35.0只在1999年出现,而毒性类型I4.1和I14.1只在2000年出现。两个季节中病圃的毒性类型组成有所差异,早季有1个毒性类型(I35.1)在晚季未出现,晚季有4个毒性类型(I10.1、I31.1、I32.1、I21.1)在早季中未出现,优势毒性类型早季的I14.1变为晚季的I20.1,毒性类型组成也有很大差异,且晚季的比早季的丰富。 相似文献
5.
油菜野芥NSa细胞质雄性不育系的特异性分子鉴定 总被引：2，自引：0，他引：2
常规细胞质类型鉴定方法花费时间长、工作量大、鉴定效率低、应用性较差。基于基因组重复序列的PCR技术(rep-PCR)在重复序列丰富的线粒体和原核生物的基因组鉴定中效果较好, 本研究对8份油菜资源的细胞质进行分子鉴定,结果表明rep-PCR可以明确区分甘蓝型油菜中常见的6种雄性不育细胞质。同时对甘蓝型油菜和野芥(Sinapis arvensis)体细胞杂交创建的、育性较为稳定的NSa野芥雄性不育胞质进行了分子特异性鉴定,获得了两条NSa不育胞质的特征DNA条带。但波里马和萝卜质不育细胞质的特异性引物在NSa中不能扩增出特异性片段,说明NSa不属于这两种细胞质类型。本研究结果为该不育胞质系统的利用和知识产权保护提供了理论依据和技术支撑。 相似文献
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Said M.S. Massomo Hanne Nielsen Robert B. Mabagala Keld Mansfeld-Giese John Hockenhull Carmen N. Mortensen 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(8):775-789
Black rot, caused by Xanthomonas campestris pv. campestris (Xcc), is a major disease constraint to cabbage production by smallholder farmers in Africa. Variability exists within the pathogen, and yet differentiation of Xcc strains from other closely-related xanthomonads attacking crucifers is often difficult. The Biolog system, fatty acid methyl ester analysis using microbial identification system (MIS), rep-PCR and pathogenicity tests were used to identify and characterise Xcc strains from Tanzania. Great diversity was observed among Xcc strains in their Biolog and rep-PCR profiles. Specific rep-PCR genomic fingerprints were linked to some geographical areas in the country. Most of the Xcc strains were clustered in two groups based on their fatty acid profiles and symptom expression in cabbage although some deviant strains were found. Each of the methods allowed a degree of identification from species, pathovar to the strain level. Biolog and MIS identified all Xcc strains at least to the genus level. Additionally, Biolog identified 47% of Xcc strains to the pathovar and 43% to strain level, whereas MIS identified 43% of the strains to pathovar level. In the absence of a database, the utility of rep-PCR for routine diagnosis of strains was limited, although the procedure was good for delineation of Xcc to the strain level. These findings indicate the existence of Xcc strains in Tanzania that are distinct from those included in Biolog and MIS databases. The limitations noticed warrant continued improvement of databases and inclusion of pathogenicity testing, using universally susceptible cultivars, as an integral part of strain identification. 相似文献
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M. Scortichini U. Marchesi M.T. Dettori L. Angelucci M.P. Rossi C. Morone 《European journal of plant pathology / European Foundation for Plant Pathology》2000,106(2):147-154
Forty strains of Pseudomonas avellanae isolated from hazelnut (Corylus avellana L.) trees in the Langhe district of Italy were compared with 15 strains collected from various geographic areas. All strains were assessed by rep-PCR genomic fingerprinting using ERIC, REP and BOX primer sets. Cluster analysis was performed by means of UPGMA. To check the possible differential virulence of the strains, pathogenicity tests were carried out by inoculating leaf scars of hazelnut trees in early autumn. Cluster analysis indicated that, during a four-year study, at least five groups of strains were isolated from different hazelnut orchards located in the small district of Langhe. Two groups were isolated from the same twig. Such strains showed around 20% similarity with other P. avellanae strains collected from northern Greece and central Italy. The strains from Langhe were less aggressive to hazelnut than strains from northern Greece and central Italy. These results and previous genomic characterizations indicate a possible correlation between genomic profile type and regional geographic distribution of P. avellanae strains. In addition, the genetic variability found in the strains from Langhe indicates that such populations are older than the more homogenous P. avellanae populations from other regions. 相似文献
9.
为明确四川省猕猴桃溃疡病菌丁香假单胞菌猕猴桃致病变种(Pseudomonas syringae pv. actinidiae,Psa)的遗传多样性及群组划分与地理来源的相关性。以四川省不同地理来源的40个Psa菌株为研究试材,用rep-PCR技术进行分子标记,NTSYS软件分析UPGMA聚类。3对rep-PCR检测引物(REP、ERIC和BOX)共获得42个位点,其中38个为多态位点,占90.5%。UPGMA聚类结果显示,以相似系数为0.70阀值时,40个Psa菌株被分为2个类群(Ⅰ、Ⅱ),其中85.0%的菌株属于第Ⅱ类群;在相似性系数为0.80时,第Ⅰ类又可分为2个亚类(Ⅰ-1、Ⅰ-2),第Ⅱ类则分为5个亚类(Ⅱ-1、Ⅱ-2、Ⅱ-3、Ⅱ-4、Ⅱ-5),菌株无明显的采集地聚类。以上结果表明,四川省各地区的猕猴桃溃疡病菌菌株具有较高的遗传多样性,但其遗传变异与菌株地理来源无明显相关性。 相似文献
10.
构建稻瘟病菌有性后代随机群体是研究目的基因遗传特点,乃至克隆目的基因的重要基础,但是在建立有性后代随机群体时,可能会有无性后代污染。采用先分离单个子囊,待其长成菌落并产生分生孢子后,再分离单个萌发的分生孢子的方法构建稻瘟病菌有性后代随机群体。利用基于重复DNA序列Pot2的rep-PCR方法对分离得到的有性后代进行DNA指纹分析,并评价构建的稻瘟病菌有性后代群体的质量。结果表明,构建的有性后代随机群体共包含176个后代。每个后代个体的DNA指纹图谱均与两亲本的DNA指纹图谱不一致;有性后代之间的DNA指纹图谱也彼此不一样,说明得到的有性后代个体都是由子囊孢子萌发形成的,且分离自不同的子囊。GUY11的rep-PCR扩增片段中的5个特异性片段的分离比例也都符合1:1的期望值,是按单个位点标记分离的,与已知的结果相吻合,说明有性后代随机群体的质量较高,不存在偏离现象,是一个较为理想的群体。同时,研究结果还得出基于Pot2的rep-PCR方法可以用来快速评价稻瘟病菌有性后代群体的质量。 相似文献