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EN
The averaged genomic similarities based on multilocus randomly amplified polymorphic DNA (RAPD) were calculated for eight species representing three sections of the genus Vicia: faba, bithynica and narbonensis. The frequency of appearance of the sequences corresponding to 25 decamers selected at random from genomes of different Fabace species was checked, and a high correlation with the frequency observed for Vicia allowed us to assume their similar weight in typing Vicia species. The RAPD-based similarity coefficients compared with those related to whole genome hybridization with barley rDNA and those based on restriction fragment length polymorphism (RFLP) revealed similar interspecies relationships. The averaged RAPD-based similarity coefficient (Pearson's) was 0.68 for all the species, and was sectionspecific: 0.43 (bithynica), 0.50 (faba) and 0.73 (narbonensis). The averaged similarity coefficient for V. serratifolia (0.63) placed it apart from the rest (0.75) of its section. The results correspond to the interspecies relationships built upon non-genetic data. The averaged similarity coefficient for particular RAPD was related to the presence and type of tandemly repeated motif in a primer: 0.7-0.8 for heterodimers (GC, AG, CA, GT, CT), 0.5-0.6 for homodimers (CC, GG) and 0.6 for no repeat, indicating the sensitivity of diversity range to the type of target sequences.
EN
A sample of Betula nana from the Linie reserve near Dąbrowa Chełmińska, have been fingerprinted using random amplified polymorphic DNA (RAPD). The high level of genetic variation was detected. All individuals had unique genotypes, supporting the generally high resolving power of RAPD’s. For the conservation strategy, information about the distribution of the genetic variation within and among populations plays very important role. Thus, extensive study in other populations of dwarf birch is needed.
EN
Genetic variability and differentiation of six populations of Tilia rubra from Hyrcanian forests of the north of Iran were analyzed using random amplified polymorphic DNA (RAPD) markers. Seven primers pairs used to study six populations, in six localities located in at different altitude (250–2500 m a.s.l) but within the distance 50 km, provided 70 reliable bands, of which 29 (41.4%) were polymorphic. The average population diversity using the Shannon’s index (I) was 0.22 and ranged from 0.22 for Bandbon population to 0.08 for the Salahedinkola population. The mean heterozygosity varied from 0.013 to 0.06 within the populations of T. rubra. The AMOVA analysis showed a significant genetic differentiation within populations and 97% of the total variation occurred within populations and only 3% occurred among populations. Cluster analysis using the UPGMA method grouped all individuals into four clusters. The results did not correspond with the populations origin. The low inter-population differentiation and the lack of significant correlation between geographic and genetic distances suggest intensive gene flow among populations of Tilia rubra.
EN
Extended-spectrum β-lactamase (ESBL)-producing Klebsiella pneumoniae (EPKP) strains are frequently implicated in outbreaks in neonatal units. From April 2002 to January 2003, 149 neonates were colonized/infected with EPKP In the Neonatal Clinic of the Teaching Hospital at the Medical University of Gdansk, Poland. A novel assay based on suppression of PCR, ADSRRS-fingerprinting, was successfully evaluated for typing EPKP isolates. The results showed that the genotypes of all outbreak-related strains were identical, which suggested that the outbreak originated from a single clone. This conclusion was confirmed by using different methods - RAPD and PFGE. The outbreak was stopped by adopting improved hygiene and instituting outbreak control measures.
EN
The genetic relations between Büzgülü grape ecotypes (Vitis vinifera L.) grown in different regions of Turkey were investigated by RAPD analysis. Of 50 decamer primers tested, 20 were used in the study, and 17 yielded clear and reproducible polymorphic bands. Differences between ecotypes were analyzed statistically. The similarity index was lowest (0.601) between Etli Büzgülü (collection no. 619, from Antalya province) and Büzgülü (no. 572, Eskisehir prov.), and highest (0.879) between Sik Büzgülü (no. 516, Konya prov.) and Büzgülü (no. 738, Kütahya prov.). The data matrix indicated genetic distances ranging up to 0.038, although most were under 0.03. Phylogenetic trees obtained by UPGMA and neighbor-joining methods basically resembled each other, with some differences. The results from RAPD analysis correlated with some morphological characteristics. This study of Turkish grape germplasm suggests that the geographical and ecological distribution of the plants contributes to higher genetic similarity.
EN
RAPD (randomly amplified polymorphic DNA) and ISSR (intersimple sequence repeat) fingerprinting on HpaII/MspI-digested genomic DNA of nine elite japonica rice cultivars implies inter-cultivar DNA methylation polymorphism. Using both DNA fragments isolated from RAPD or ISSR gels and selected low-copy sequences as probes, methylation-sensitive Southern blot analysis confirms the existence of extensive DNA methylation polymorphism in both genes and DNA repeats among the rice cultivars. The cultivar-specific methylation patterns are stably maintained, and can be used as reliable molecular markers. Transcriptional analysis of four selected sequences (RdRP, AC9, HSP90 and MMR) on leaves and roots from normal and 5-azacytidine-treated seedlings of three representative cultivars shows an association between the transcriptional activity of one of the genes, the mismatch repair (MMR) gene, and its CG methylation patterns.
EN
A number of morphological, physiological and phenological traits are known to improve the performance of rice challenged by drought. Root morphological traits and stress-induced response form important components of drought tolerance. Enhancing grain yield remains the principal objective of most breeding programs. Interaction between primary traits poses a formidable challenge while dealing with grain yield under stress. The evaluation of root morphology at three different growth stages and grain yield along with related characteristics under contrasting moisture regimes was made using nine backcrosses along with their parent and standard checks. The backcrosses invoved transgressant double haploid lines derived from IR64 and Azucena with IR64. Marked genotypic differences were observed for all root morphology as well as grain yield related characteristics across the sampling dates as revealed by individual and combined ANOVA. Among the nine backcrosses studied in this experiment, the BC1F2 population of P124 x IR64 were evaluated for forwarding based on their performance with respect to maximum root length and grain yield under both well-watered and low-moisture stress conditions. Sixtynine plants - ten percent of the backcross population - were selectively genotyped using RAPD primers. Under well-watered conditions two RAPD markers showed strong linkage to QTLs for maximum root length evaluated under ww conditions. Two other markers could explain the considerable amount of variation in MRL under LMS. One of the markers identified under low-moisture stress conditions was also able to explain variability in maximum root length in the mean environment.
EN
The aim of our research was to evaluate the genetic diversity among 25 commercial varieties registered in Poland and 145 landraces of Phaseolus vulgaris var. nanus Asch. (the dwarf common bean) and Phaseolus coccineus L. (the runner bean) maintained in the National Centre of Plant Genetic Resources in Radzików. An additional goal of this study was to compare the precision and efficiency of two techniques of PCR (RAPD and AFLP), used to estimation the genetic diversity of bean. The breeding varieties of bean were registered in the period between 1950 and 2000. The landraces, collected during expeditions conducted from 1985 to 1988, mainly originated from the eastern and southern part of Poland. In the plant genetic diversity research of RAPD and AFLP markers are commonly used. Complex electrophoresis pictures of DNA fragments were taken, and revealed a considerable polymorphism. The polymorphic fragments were obtained on the basis of 6 differentiating primers using the RAPD method and 15 differentiating primers using the AFLP method. P. vulgaris and P. coccineus accessions formed distinct groups. Each of the RAPD and AFLP analyses allowed for the unique distinguishing of all accessions.
EN
In this study, we evaluated three PCR-based methods for the molecular typing of nonpathogenic Fusarium oxysporum isolates: random amplified polymorphic DNA (RAPD), polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) and amplified fragment length polymorphism (AFLP). The analyses were performed using 64 isolates of F. oxysporum collected from cotton-producing areas in Egypt. A number of polymorphic RAPD, PCR-RFLP and AFLP bands were scored in all isolates and the genetic similarity among them was assessed. Clustering analysis separated the isolates into two main groups, with similarities ranging from 87 to 100% for RAPD, 80 to 100% for PCR-RFLP and 88 to 97% for AFLP, respectively. The obtained data suggested that all three types of markers are equally informative, but the three assays differed in the amount of detected polymorphic bands. AFLP fingerprinting was also found to be more differentiating than other techniques for the typing of F. oxysporum populations.
EN
There are many unsolved taxonomic problems at the intraspecific level in the genus Thalictrum (Ranunculaceae), which may be clarified using molecular systematics methods. No molecular systematics methods have been applied yet to the genus Thalictrum; this study analyzes different leaf tissue preservation and DNA isolation techniques, and the applicability of RAPD. A modified DNA isolation procedure using solution of laundry detergent as a detergent buffer system was the most suitable, especially for dealing with large samples. Since the use of differently preserved leaf tissues simultaneously with fresh leaf tissue may improve sampling in taxonomic research, and because the RAPD technique is sensitive to different factors, the possible drawbacks of using such tissues in RAPD analyses were checked. Of the four preserved leaf tissues, only DNA from silica gel-preserved leaf tissue gave suitably reliable RAPD results to be used with fresh leaf tissue in more extensive taxonomic research. Differently preserved leaf tissues are very problematic starting materials for simultaneous use with fresh leaf tissue in the same RAPD analysis. If differently preserved leaf tissues are to be used and reliable results are to be obtained, research techniques similar to those used in this paper should be applied.
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