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RAPD
About: RAPD is a research topic. Over the lifetime, 15960 publications have been published within this topic receiving 360391 citations.
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27 Nov 1992
110 citations
TL;DR: The results are discussed with reference to the capability of the analytical procedures used to aid both identification and strain typing of streptococci, as well as the taxonomic structure of the species Strep.
Abstract: Streptococci from different collections and dairy materials were characterized by conventional and molecular methods. After amplification of the 16S–23S rDNA spacer region, all the strains referable to the genus Streptococcus exhibited a single polymerase chain reaction (PCR) product, allowing their differentiation from enterococci. Cleaving this PCR product with Hae III, two different restriction patterns could be observed, allowing Streptococcus salivarius DSM 20560T, Strep. thermophilus NCDO 822 and two strains of Streptococcus spp. to be gathered in one group and all the other strains in another. In order to achieve strain typing, all the cultures were investigated by random amplified polymorphic DNA (RAPD)-PCR analysis employing two selected primers. The results were treated by cluster analysis, appearing significantly consistent with both the taxonomic position and the origin of the strains. Pulsed-field gel electrophoresis (PFGE) of Sma I digests of the genomic DNA from 11 representative strains with decreasing levels of RAPD similarity allowed their diversity to be confirmed, even though RAPD-PCR proved to be less discriminating than PFGE analysis. The results are discussed with reference to the capability of the analytical procedures used to aid both identification and strain typing of streptococci, as well as the taxonomic structure of the species Strep. thermophilus .
110 citations
TL;DR: It is concluded that the isolates tested belonging to the species M. anisopliae, as assessed on morphological grounds, represent a very diverse genetic group and RAPD markers may be useful for the tracking of specific biocontrol strains in the field.
Abstract: Metarhizium anisopliae isolates from several insect hosts and from various sugar cane growing areas of Queensland, Australia, were examined for genetic diversity using random amplified polymorphic DNA (RAPD) markers. Thirty isolates of M. anisopliae var. anisopliae and one isolate of M. anisopliae var. majus were examined. Ten randomly chosen 10mer or 11mer primers were used and RAPD banding patterns were compared. Thirty distinct genotypes could be distinguished amongst the 31 isolates tested on the basis of RAPD patterns. Six of the isolates classified as M. anisopliae var. anisopliae exhibited closer similarity to the M. anisopliae var. majus isolate than to other anisopliae strains tested. Isolates exhibiting similar (> 80% similarity) RAPD profiles tended to be isolated from the same geographic area and evidence for the persistence of particular fungal genotypes in specific geographical localities was obtained. Pathogenicity assays suggested that, in some instances, RAPD groupings may also indicate insect host range. The mean similarity amongst isolates measured by band sharing in all pairwise comparisons was 41% and the most distinct pair of isolates shared only 9% of their RAPD bands. We conclude that the isolates tested belonging to the species M. anisopliae, as assessed on morphological grounds, represent a very diverse genetic group. The results also suggest that RAPD markers may be useful for the tracking of specific biocontrol strains in the field.
109 citations
TL;DR: It is proposed that the mandarin group is a single species, C. reticulata Blanco, composed of several genetically different individuals and a great number of hybrids, rather than a large number of species as proposed by some taxonomic studies.
Abstract: RAPD markers were used to evaluate genetic similarity among 35 mandarin accessions, including 10 species and 7 hybrids One octamer and twenty-two decamer primers produced 109 RAPDs, 45 of which were polymorphic Jaccard coefficient was used to calculate genetic similarity, and UPGMA to generate the phenogram The RAPDs obtained were sufficient to generate some accession-specific markers, and to separate these accessions by clustering them into several groups, many of them according to Tanaka's or Webber's systematic units The genetic similarity within the mandarin group is high (GJ = 077), and suggests that cultivated mandarins have a narrow genetic base The genetic similarity of mandarins to other true citrus species (Citron [C medica L] and Pummelo [C grandis Osbeck]) was much lower (minimum GJ = 027) We propose that the mandarin group is a single species, C reticulata Blanco, composed of several genetically different individuals and a great number of hybrids, rather than a large number of species as proposed by some taxonomic studies
109 citations
TL;DR: Genetic linkage maps for two apricot cultivars have been constructed using AFLP, RAPD, RFLP and SSR markers in 81 F1 individuals from the cross 'Goldrich' × 'Valenciano', the most-important virus affecting Prunus species.
Abstract: Genetic linkage maps for two apricot cultivars have been constructed using AFLP, RAPD, RFLP and SSR markers in 81 F1 individuals from the cross 'Goldrich' × 'Valenciano'. This family segregated for resistance to 'plum pox virus' (PPV), the most-important virus affecting Prunus species. Of the 160 RAPD arbitrary primers screened a total of 44 were selected. Sixty one polymorphic RAPD markers were scored on the mapping population: 30 heterozygous in 'Goldrich', 19 heterozygous in 'Valenciano', segregating 1:1, and 12 markers heterozygous in both parents, segregating 3:1. A total of 33 and 19 RAPD markers were mapped on the 'Goldrich' and 'Valenciano' maps respectively. Forteen primer combinations were used for AFLPs and all of them detected polymorphism. Ninety five markers segregating 1:1 were identified, of which 62 were heterozygous in the female parent 'Goldrich' and 33 in the male parent 'Valenciano'. Forty five markers were present in both parents and segregated 3:1. A total of 82 and 48 AFLP markers were mapped on the 'Goldrich' and 'Valenciano' maps. Twelve RFLPs probes were screened in the population, resulting in five loci segregating in the family, one locus heterozygous for 'Valenciano' and four heterozygous for both, segregating 1:2:1. Of the 45 SSRs screened 17 segregated in the mapping family, resulting in seven loci heterozygous for the maternal parent and ten heterozygous for both, segregating 1:2:1 or 1:1:1:1. A total of 16 and 13 co-dominant markers were mapped in the female and male parent maps respectively. A total of 132 markers were placed into eight linkage groups on the 'Goldrich' map, defining 511 cM of the total map-length. The average distance between adjacent markers was 3.9 cM. A total of 80 markers were placed into seven linkage groups on the 'Valenciano' map, defining 467.2 cM of the total map-distance, with an average interval of 5.8 cM between adjacent markers. Thirty six marker loci heterozygous in both parents revealed straightforward homologies between five linkage groups in both maps. The sharka resistance trait mapped on linkage group 2. The region containing sharka resistance is flanked by two co-dominant markers that will be used for targeted SSR development employing a recently constructed complete apricot BAC library. SSRs tightly linked to sharka resistance will facilitate MAS in breeding for resistance in apricot.
109 citations