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Amplification Patterns (amplification + pattern)
Selected AbstractsRAPD PCR for Diagnosis of Phytophthora parasitica var. nicotianae Isolates which Cause Black Shank on TobaccoJOURNAL OF PHYTOPATHOLOGY, Issue 10 2001X. G. Zhang Phytophthora parasitica var. nicotianae is the fungal pathotype of tobacco black shank (TBS, Disease severity , 2.0). Random amplified polymorphic DNA (RAPD) analysis was used to differentiate isolates which cause TBS from those which do not. Greenhouse assays combined with zoospore inoculation were performed to assess the virulence of the fungal isolates, and the results were compared with the RAPD pattern analysis. The RAPD results exhibited total correlation with the virulence assay results. Amplification patterns generated by RAPD reactions were used to generate a phenogram depicting the genetically distinct nature of the cluster defined by the TBS isolates. This cluster was exclusive and distinct from P. parasitica var. nicotianae isolates which do not cause TBS. Thus, RAPD proved to be a sensitive and highly reliable method for quickly identifying fungal pathotypes which cause TBS. [source] Isolation and characterization of microsatellite loci in Bemisia tabaciMOLECULAR ECOLOGY RESOURCES, Issue 1 2003P. J. De Barro Abstract Bemisia tabaci (Hemiptera: Aleyrodidae) is a haplo-diploid species with a global distribution demonstrating strong geographical structure with eight recognizable genetic groups. Fifteen microsatellite loci (335 alleles, 6,44 alleles per locus) were derived from four of the eight groups and were then screened across 33 populations. These loci clearly differentiate the populations. The microsatellites amplified best in individuals from genetic groups rep-resenting the Mediterranean, Middle East, Asia (three groups) and Australasia/Oceania and amplified less well with populations from sub-Saharan Africa and the New World. This differential amplification pattern is a direct result of the relatedness to the microsatellite source material. [source] Genetic characterization of Erwinia amylovora strains by amplified fragment length polymorphismJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2004A. Rico Abstract Aims:,Erwinia amylovora is one of the most important pathogens of pear and apple and is subject to strict quarantine regulations worldwide, although its patterns of dispersal are largely unknown. Previous attempts to fingerprint E. amylovora strains by molecular techniques have detected very little polymorphism because of the high genetic homogeneity of this bacterium. Our aim was to establish and test a typing method to quantify genetic diversity among strains of this plant pathogen. Methods and Results:, Twenty-two strains from different hosts and geographical locations were examined by PCR fingerprinting with four primers and by amplified fragment length polymorphism (AFLP) with four selected combinations of primers with a single base extension. PCR fingerprinting revealed little polymorphism producing the same amplification patterns for 17 strains, while the combined AFLP patterns yielded 78 polymorphic bands (34% of total bands) and allowed the differentiation of all but two strains. Clustering of strains in the resulting dendrogram was not correlated with host, year or country of isolation, and questions previous genealogies based on PFGE patterns. Conclusions:, The AFLP technique allowed the detection of an unprecedented number of genetic markers in E. amylovora and proved to be the most useful tool so far for discriminating among strains of this pathogen. The results obtained in this study strongly suggest the occurrence of multiple introductions of the pathogen in Spain and other European countries. Significance and Impact of the Study:, A major limitation in understanding the ecology of fire blight is the lack of typing techniques with a high power of discrimination. This study demonstrates the high resolution and the usefulness of the AFLP technique to differentiate among E. amylovora strains. [source] Isolation and characterization of the first eight microsatellite loci in Gammarus fossarum (Crustacea, Amphipoda) and cross-amplification in Gammarus pulex and Gammarus orinosMOLECULAR ECOLOGY RESOURCES, Issue 5 2009DELPHINE DANANCHER Abstract We characterized the first microsatellite markers for Gammarus fossarum. Eight loci gave satisfactory amplification patterns in two stream populations (Southern France) with number of alleles ranging from 2 to 10 and expected heterozygosity from 0.076 to 0.857. We performed cross-amplification in two closely related gammarid species, Gammarus pulex and Gammarus orinos. Among the eight tested microsatellite loci, four correctly amplified in G. pulex and three in G. orinos. [source] | ||||||||||