4,548 research outputs found
Differences in growth, survival and phenology in Quercus rubra and Q. ellipsoidalis seedlings
No full textRelated oak species with different ecological requirements often hybridize where they co-occur. Even though interspecific gene flow is consideredto be common in closely relatedoaks, species identity in sympatric oak species with different local adaptations is generally maintained with a low number of hybrids andintrogressive forms in the adult tree generation. Quercus rubra and Q.ellipsoidalis offer a goodmod el to study characters that are related to different local adaptations and reproductive isolation of the species. Both species are interfertile, but grow in different micro-environments with Q.ellipsoidalis as the most drought tolerant red oak species occurring often on very dry sites. In an earlier study, genetic assignment analysis at 15 highly variable microsatellite markers revealeda low number of hybrids (0-2%) andintrogressive forms (0-4%) in neighboring Q.ellipsoidalis and Q.rubra populations in both the adult tree and seedling generation. In the present study, pronounced differences in growth and survival, the timing of bud burst and leaf senescence between seedlings of both species in a common garden experiment suggested reproductive isolation between species and genetic differences in fitness-related traits. Future studies should focus on the analysis of fitness traits in parental environments using reciprocal transplant studies
Nucleotide diversity of candidate genes involved in bud burst within and among natural populations of sessile oak (Quercus petraea (Matt.) Liebl.)
No full textFive natural populations of sessile oak were sampled along an altitudinal gradient (100 to 1600 meters) in the French Pyrenees in order to validate functionally important SNPs (single nucleotide polymorphisms) in candidate genes involved in bud burst, by testing their adaptive values through their d..
Growth traits of Quercus macranthera subsp. syspirensis populations in Turkey and their associations with environmental variables
No full textDifferences in growth traits among twelve populations across the Quercus macranthera subsp. syspirensis (ispir oak) distribution range in Turkey were investigated in a common garden seedling trial. The study revealed considerable variation in growth traits across the studied ispir oak populations. T..
Genetic diversity of Mansonia altissima A. Chev. under different regimes of human impact in the Akure forest reserve, Nigeria
No full textMansonia altissima is an important West African timber tree species. For the purpose of examining the effect of human impact on its genetic diversity, genetic diversity and spatial genetic structure of the species under different regimes of human impact were investigated in the Akure Forest Reserve,..
Introgression of genes between two hybridizing red oak species with different drought tolerance
No full textHybridizing species that maintain different local adaptations despite interspecific gene flow are models for the discovery of genes involved in reproductive isolation and adaptive divergence of species. Quercus rubra L. and Quercus ellipsoidalis E.J. Hill are two interfertile red oak species with di..
Indigenous knowledge, traditional management and genetic diversity of the endogenous agroforestry species ackee (Blighia sapida) in Benin
No full textBlighia sapida (ackee) is a multipurpose species important for the livelihoods of rural populations and is traditionally managed by farmers in different land use systems. This study first addresses farmers' knowledge on management and perception of variation of the species among different ethnic gro..
Development of genomic microsatellites in Gleditsia triacanthos (Fabaceae) using Illumina sequencing
No full textPremise of the study: Fourteen genomic microsatellite markers were developed and characterized in honey locust, Gleditsia triacanthos, using Illumina sequencing. Due to their high variability, these markers can be applied in analyses of genetic diversity and structure, and in mating system and gene ..
Introgression of genes between two hybridizing red oak species with different drought tolerance
No full textHybridizing species that maintain different local adaptations despite interspecific gene flow are models for the discovery of genes involved in reproductive isolation and adaptive divergence of species. Quercus rubra L. and Quercus ellipsoidalis E.J. Hill are two interfertile red oak species with di..
Strategies to identify adaptive genes in hybridizing trees like oaks and poplars
Full text linkEcologically divergent, hybridizing species such as oaks and poplars provide models to identify genomic regions under selection and adaptive alleles that are transferred between species in hybrid zones. Oaks show patterns of genomic divergence characteristic for early stages of speciation with gene flow, in which large genomic regions are homogenized by interspecific gene flow interspersed by smaller regions (outlier regions) with high interspecific differentiation as result of divergent selection. These outlier regions can be identified using genome scans in hybrid zones and anchored to the Quercus robur genome sequence which will become available in the near future. Combined outlier and association genetic approaches can assess the role of individual genes in outlier genomic regions in adaptive trait variation. In contrast, hybridizing poplar species show a pattern of genomic divergence with large genomic regions of high interspecific differentiation punctuated by smaller regions of low differentiation as the result of interspecific gene flow. Genome scans in multiple hybrid zones of interfertile poplar species and in populations outside the area of sympatry will allow for the identification of genes that are exchanged between species by interspecific gene flow using the Populus trichocarpa genome sequence as a reference. Again association genetic approaches can be used for the characterization of variation in these introgressed genes with adaptive trait variation. In the present paper, the application of genomic approaches to identify genes for adaptive species divergence and reproductive isolation, and introgressed genes between species is discussed
Erfassung der adaptiven genetischen Variation der Eiche im Hinblick auf den Klimawandel
No full textClimate change is projected to lead to a major reorganization of our forests. For example, higher annual mean temperatures, longer growth seasons and drier summers are predicted for many parts of central and southern Europe, and in North America. In order to understand the genetic adaptation to clim..
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