Search results for "Analysis of molecular variance"
showing 9 items of 9 documents
Morphological, chemical, and genetic diversity of wild myrtle(Myrtus communis L.) populations in Sicily
2016
Myrtus communis L. İs a shrub widespread in the Mediterranean area. The interest in this species is growing, mainly due to its pharmacological and aromatic properties. The overexploitation of wild populations induced increasing degradation of plant cover with serious risk of loss of genetic diversity. This research explored the morphological, chemical, and genetic diversity of wild myrtle populations in Sicily, with the aim to provide a first characterization of a core collection of 36 accessions from 7 localities for future domestication programs. Amplified fragment length polymorphism fingerprinting generated 152 polymorphic fragments. STRUCTURE analysis identified three genetic clusters …
Microsatellite analysis of red mullet Mullus barbatus (Perciformes, Mullidae) reveals the isolation of the Adriatic Basin in the Mediterranean Sea
2009
AbstractMaggio, T., Lo Brutto, S., Garoia, F., Tinti, F., and Arculeo, M. 2009. Microsatellite analysis of red mullet Mullus barbatus (Perciformes, Mullidae) reveals the isolation of the Adriatic Basin in the Mediterranean Sea. – ICES Journal of Marine Science, 66: 1883–1891. The red mullet Mullus barbatus is commercially one of the most important demersal fish resources in the Mediterranean. Molecular data on its genetic population structure throughout the Mediterranean are reported. Six microsatellite loci displayed a high degree of expected heterozygosity and a high allele number per locus. The Hardy–Weinberg equilibrium test revealed an overall tendency towards heterozygote deficiency, …
Variation of haplotype distributions of two genomic regions of Citrus tristeza virus populations from eastern Spain.
2003
Genetic variation in natural populations of Citrus tristeza virus (CTV) was studied using haplotypes detected by single-strand conformation polymorphism (SSCP) analysis of two genomic regions (p20 gene and segment A, located in ORF1a). Analysis of 254 samples from 125 trees, collected at 12 different sites, yielded 8 different haplotypes for p20 and 5 for segment A. The most frequent haplotype of p20 was predominant at all sites, but several sites differed in the predominance of segment A haplotypes. At most sites, the homozygosity observed for the p20 gene tended to be higher than expected in a neutral evolution, whereas the opposite was true for segment A. Comparison of the populations at…
Differential cycles of range contraction and expansion in European high mountain plants during the Late Quaternary: insights from Pritzelago alpina (…
2003
Nuclear DNA sequence variation of the internal transcribed spacer (ITS) and amplified fragment length polymorphisms (AFLPs) were used to illuminate the evolutionary history of Pritzelago alpina, a herbaceous perennial of (sub)alpine to nival habitats of the European high mountains. Maximum likelihood analysis of ITS sequences of P. alpina, Hornungia petraea and Hymenolobus procumbens (the 'Pritzelago alliance') resolved P. alpina and H. petraea as sister taxa. ITS divergence estimates support an origin for P. alpina in the Late Tertiary, while intraspecific diversification started in the Late Quaternary (0.4-0.9 million years ago). AFLP analysis of 76 individuals of P. alpina, representing …
Analysis of population genetic structure and variability using RAPD markers in the endemic and endangered Limonium dufourii (Plumbaginaceae)
1998
Limonium dufourii (Plumbaginaceae) is a triploid species, with apomictic reproduction, endemic to the east mediterranean coast of Spain, where it is present in only six populations with a few individuals in most of them. L. dufourii is included in the Red List of Endangered Species by the IUCN. Genetic variation and population structure in this species has been studied using RAPDs. Twelve different primers provided 124 reliable bands of which 33 were polymorphic among the 165 individuals analysed. Those polymorphic bands were able to define 44 different patterns, of which all but six were present in only one population. Several methods for statistical evaluation have been used for intra- an…
Genetic diversity ofNarcissus tortifolius, an endangered endemic species from Southeastern Spain
2015
AbstractIn this work, we analyzed inter-simple sequence repeat markers from 10 populations (298 individuals) spanning the whole distribution range of the endemic Narcissus tortifolius. We assessed genetic variation levels and distribution by estimates of genetic diversity, analysis of molecular variance (AMOVA), principal coordinates and Bayesian methods. N. tortifolius showed moderate genetic diversity at intrapopulation level and low genetic differentiation of populations. In general, Almerian populations showed slightly higher levels of genetic diversity than Murcian populations. Our results indicate that habitat fragmentation has not caused genetic depauperation in N. tortifolius but di…
An assessment of genetic relationships within the genus Digitalis based on PCR-generated RAPD markers
2000
RAPD markers were used to study inter-specific variation among six species of the genus Digitalis: D. obscura, D. lanata, D. grandiflora, D. purpurea, D. thapsi and D. dubia, and the hybrid D. excelsior (D. purpurea×D. grandiflora). A total of 91 highly reproducible bands amplified with four arbitrarily chosen decamer primers were obtained. Homology of the co-emigrating RAPD markers was tested by blot hybridisation and sequencing of selected bands. The application of a range of statistical approaches for RAPD data analysis, including distance and parsimony methods, family clustering and the analysis of molecular variance (AMOVA), indicated that these molecular markers were taxonomically inf…
The haplotype distribution of two genes of citrus tristeza virus is altered after host change or aphid transmission.
1999
Genetic variability of citrus tristeza virus (CTV) was studied using the haplotypes detected by single-strand conformation polymorphism (SSCP) analysis of genes p18 and p20 in six virus populations of two origins. The Spanish group included a CTV isolate and subisolates obtained by graft-transmission to different host species. The other included two subisolates aphid-transmitted from a single Japanese isolate. The homozygosity observed for gene p20 was always significantly higher than that expected under neutral evolution, whereas only three populations showed high homozygosity for p18, suggesting stronger host constraints for p20 than for p18. Sequential transmissions of a Spanish isolate …
Epidemic dynamics of two coexisting hepatitis C virus subtypes.
2006
Hepatitis C virus (HCV) infection affects about 3 % of the human population. Phylogenetic analyses have grouped its variants into six major genotypes, which have a star-like distribution and several minor subtypes. The most abundant genotype in Europe is the so-called genotype 1, with two prevalent subtypes, 1a and 1b. In order to explain the higher prevalence of subtype 1b over 1a, a large-scale sequence analysis (100 virus clones) has been carried out over 25 patients of both subtypes in two regions of the HCV genome: one comprising hypervariable region 1 and another including the interferon sensitivity-determining region. Neither polymorphism analysis nor molecular variance analysis (att…