1,827 research outputs found
Chloroplast haplotypes of Northern Red Oak (Quercus rubra L.) stands in Germany suggest their origin from northeastern Canada
Get PDFСтатья из журнала.Northern red oak (Quercus rubra L.) is one of the most important foreign tree species in Germany and considered as a major candidate for prospective sustainable forestry in the face of climate change. Therefore, Q. rubra was subject of many previous studies on its growth traits and attempts to infer the origin of various populations of this species using nuclear and chloroplast DNA markers. However, the exact geographic origin of German red oak stands has still not been identified. Its native range widely extends over North America, and the species can tolerate a broad range of environmental conditions. We genotyped individual trees in 85 populations distributed in Germany and North America using five chloroplast microsatellite and three novel chloroplast CAPS markers, resulting in the identification of 29 haplotypes. The new marker set enabled the identification of several new red oak haplotypes with restricted geographic origin. Some very rare haplotypes helped us narrow down the origin of Q. rubra stands in Germany, especially some stands from North Rhine-Westphalia, to the northern part of the species' natural distribution area including the Peninsula of Nova Scotia, where the most similar haplotype composition was observed, compared to distinct German stands. © 2020 by the authors
Marker allozyme genes and alleles for differentiation of <i>Populus deltoides</i>, <i>P</i>. <i>nigra</i>, <i>P</i>. <i>maximowiczii</i>, and their interspecific hybrids
No full text Horizontal starch gel electrophoresis of enzymes was used to compare the allelic constitution of individuals of Populus deltoides Marsh., P. nigra L., P. maximowiczii Henry, P. ×canadensis Moench, and F1 progeny of controlled crosses. Forty allozyme loci coding for 12 enzyme systems in root tips were observed. Populus deltoides, P. nigra, and P. maximowiczii were genetically distinct from each other. Each of these species had unique alleles at many loci, and one or two of these species also had some species-specific genes. Populus deltoides, P. nigra, and P. maximowiczii could be distinguished by mutually exclusive or unique alleles at any of the four allozyme loci Aco-2, Lap-1, Lap-2, and Pgi-2. Additionally, allozymes of Pgm-1, 6-Pgd-2, 6-Pgd-4, and 6-Pgd-5 could be used as markers to distinguish P. deltoides from P. nigra and P. maximowiczii, allozymes of Mdh-2, Per-3, Pgm-2, and Pgm-3 to distinguish P. nigra from P. deltoïdes and P. maximowiczii, and allozymes of Got-1, Got-4, and Pgi-1 to distinguish P. maximowiczii from P. deltoides and P. nigra. The observed marker allozyme genes and alleles can be effectively used for discriminating among the three Populus species and their interspecific hybrids, and identification and verification of paternity of progeny of single-pair and interspecific pollen-mix controlled crosses. Biochemical and molecular markers have significance in genetics, breeding, and systematics of these Populus species. Key words: Populus, allozymes, diagnostic genes and alleles, species and hybrid differentiation, enzyme electrophoresis. </jats:p
Allozyme divergence and evolutionary relationships among <i>Populus deltoides</i>, <i>P</i>. <i>nigra</i>, and <i>P</i>. <i>maximowiczii</i>
No full text Horizontal starch gel electrophoresis of enzymes was used to study genetic divergence among Populus deltoides Marsh. (section Aigeiros Duby, Salicaceae), P. nigra L. (section Aigeiros), and P. maximowiczii Henry (section Tacamahaca Spach.) at 37 to 40 allozyme loci coding for 12 enzyme systems in root tips. These three Populus species were genetically distinct from each other. Populus deltoides, P. nigra, and P. maximowiczii had mutually exclusive alleles at two loci, and each of these species had unique alleles at many loci. Certain allozyme loci were detected only in one or two of these species. Frequency distributions of allozyme loci were bimodal with respect to genetic identity for comparisons between any two species. The mean genetic distance was 0.36 ± 0.10 between P. deltoides and P. nigra, 0.39 ± 0.09 between P. deltoides and P. maximowiczii, and 0.34 ± 0.10 between P. nigra and P. maximowiczii. The enzyme electrophoretic evidence indicated a monophyletic origin of the three Populus species.Key words: poplars, genetic identity and divergence, allozymes, molecular evolution, phylogenetics. </jats:p
Paleoproteomics: An Introduction to the Analysis of Ancient Proteins by Soft Ionisation Mass Spectrometry
No full textThe field of proteomic research, analogous to genomic research, has only recently witnessed a rapid increase in its application to the study of ancient materials. Bone has been the most commonly used archaeological and paleontological resource for recovering biological information. This has most frequently been for ancient genomic analysis, but some of the potential advantages of proteomics lie in its ability to discriminate between sources of the molecules, rather than the particular species or individual. However, proteomes could be considered more dynamic, offering different types of information than otherwise available through DNA analyses. Proteins are also considered to survive for much longer periods of time than substantial lengths of DNA and therefore the development of proteomics allows for the possibility of being able to recover information much further back in time than previously thought possible. In this chapter, the progress of this area called ‘paleoproteomics’ is reviewed, highlighting some of its greatest achievements but also some of the current limitations in the field across proteins from a range of different materials
Genetic structure and identification of <i>Populus deltoides</i> clones based on allozymes
No full text The allelic constitution of 30 Populus deltoides Marsh, clones selected in Canada and United States was determined for 37 allozyme loci coding for 12 enzyme systems in root tips. The enzymes were assayed by horizontal starch gel electrophoresis. One common allele was found at each locus in all clones. The interclonal allozyme variability was controlled by 12 loci. The average proportion of heterozygous loci per clone was 4.7%. There were 23 unique multilocus genotypes among 30 clones. On average, unique genotypes differed from each other at 4.33 loci. Principal-component analysis of clonal genotypes at 12 polymorphic loci indicated 8 loci to be the most differentiating for the clones. The first three principal components accounted for 47.6% of the total variation in 12 polymorphic loci. The ordination and grouping of the clones on principal components 1, 2, and 3 portrayed clonal relationships. Clones from the same small nautral population at Cherry Beach, Ont., and five clones of P. deltoides var. occidentalis were in the same group. There was no separation of clones of two varieties, P. deltoides var. deltoides and P. deltoides var. occidentalis. These results and their usefulness were discussed with reference to identification, certification, registration, and relationships of clones.Key words: Populus deltoides Marsh., allozymes, multilocus genotypes, clone characterization, clonal relationships, poplars. </jats:p
Higher fine-scale genetic structure in peripheral than in core populations of a long-lived and mixed-mating conifer - eastern white cedar (<it>Thuja occidentalis </it>L.)
No full textAbstract Background Fine-scale or spatial genetic structure (SGS) is one of the key genetic characteristics of plant populations. Several evolutionary and ecological processes and population characteristics influence the level of SGS within plant populations. Higher fine-scale genetic structure may be expected in peripheral than core populations of long-lived forest trees, owing to the differences in the magnitude of operating evolutionary and ecological forces such as gene flow, genetic drift, effective population size and founder effects. We addressed this question using eastern white cedar (Thuja occidentalis) as a model species for declining to endangered long-lived tree species with mixed-mating system. Results We determined the SGS in two core and two peripheral populations of eastern white cedar from its Maritime Canadian eastern range using six nuclear microsatellite DNA markers. Significant SGS ranging from 15 m to 75 m distance classes was observed in the four studied populations. An analysis of combined four populations revealed significant positive SGS up to the 45 m distance class. The mean positive significant SGS observed in the peripheral populations was up to six times (up to 90 m) of that observed in the core populations (15 m). Spatial autocorrelation coefficients and correlograms of single and sub-sets of populations were statistically significant. The extent of within-population SGS was significantly negatively correlated with all genetic diversity parameters. Significant heterogeneity of within-population SGS was observed for 0-15 m and 61-90 m between core and peripheral populations. Average Sp, and gene flow distances were higher in peripheral (Sp = 0.023, σg = 135 m) than in core (Sp = 0.014, σg = 109 m) populations. However, the mean neighborhood size was higher in the core (Nb = 82) than in the peripheral (Nb = 48) populations. Conclusion Eastern white cedar populations have significant fine-scale genetic structure at short distances. Peripheral populations have several-folds higher within-population fine-scale genetic structure than core populations. Anthropogenic disturbances and population fragmentation presumably have significant effects on fine-scale genetic structure in eastern white cedar. Core populations have higher neighborhood size than peripheral populations, whereas gene flow distances are higher in peripheral than in core populations. The results of our study contribute to the knowledge of poorly-understood spatial genetic structure of core versus peripheral populations in plants. As well, the information is of significance for conservation of genetic resources of eastern white cedar and perhaps of other long-lived forest trees with mixed-mating system.</p
Genetic Structure of Natural Northern Range-Margin Mainland, Peninsular, and Island Populations of Northern Red Oak (Quercus rubra L.)
No full textPlant populations at the leading edge of the species\’ native range often exhibit genetic structure as a result of genetic drift and adaptation to harsh environmental conditions. Hence, they are likely to harbour rare genetic adaptations to local environmental conditions and therefore are of particular interest to understand climate adaptation. We examined genetic structure of nine northern marginal mainland, peninsular and isolated island natural populations of northern red oak (Quercus rubraL.), a valuable long-lived North American hardwood tree species, covering a wide climatic range, using 17 nuclear microsatellites. We found pronounced genetic differentiation of a disjunct isolated island population from all mainland and peninsular populations. Furthermore, we observed remarkably strong fine-scale spatial genetic structure (SGS) in all investigated populations. Such high SGS values are uncommon and were previously solely observed in extreme range-edge marginal oak populations in one other study. We found a significant correlation between major climate parameters and SGS formation in northern range-edge red oak populations, with more pronounced SGS in colder and drier regions. Most likely, the harsh environment in leading edge populations influences the density of reproducing trees within the populations and therefore leads to restricted overlapping of seed shadows when compared to more central populations. Accordingly, SGS was negatively correlated with effective population size and increased with latitude of the population locations. The significant positive association between genetic distances and precipitation differences between populations may be indicative of isolation by adaptation in the observed range-edge populations. However, this association was not confirmed by a multiple regression analysis including geographic distances and precipitation distances, simultaneously. Our study provides new insights in the genetic structure of long-lived tree species at their leading distribution edge.Open-Access-Publikationsfonds 202
Erratum: Genetic structure and identification of <i>Populus deltoides</i> clones based on allozymes
No full textPopulation Epigenomics: Advancing Understanding of Phenotypic Plasticity, Acclimation, Adaptation and Diseases
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