Genetic structure of natural populations of Castanea sativa in Turkey: evidence of a hybrid zone

@article{Villani1999GeneticSO,
  title={Genetic structure of natural populations of Castanea sativa in Turkey: evidence of a hybrid zone},
  author={Villani and Sansotta and Cherubini and Cesaroni and Sbordoni},
  journal={Journal of Evolutionary Biology},
  year={1999},
  volume={12}
}
This study points out the evidence of a hybrid zone between two groups of genetically differentiated populations of chestnut (Castanea sativa Mill.) in Turkey. Genetic structure, gene flow and introgression levels, based on 16 allozyme loci, were investigated on 34 population samples spanning the entire C. sativa distribution area in this country. The occurrence of the hybrid zone, located in the Bithynian region, was inferred in a group of populations showing the following genetic… 
Assessment of genetic structure within and among Bulgarian populations of the common ash (Fraxinus excelsior L.)
TLDR
Analysis of genetic variation within and between populations of the common ash from Bulgaria finds significant spatial genetic structure consistent with models of isolation by distance was detected within four out of 10 populations as well as among populations.
Estimating the genetic diversity and spatial structure of Bulgarian Castanea sativa populations by SSRs: implications for conservation
TLDR
It is hypothesized that one population is a relict from a glacial refugium; the structure of the remaining populations is probably the result of a combination of natural events and human impacts.
Role of domestication in shaping Castanea sativa genetic variation in Europe
TLDR
Randomly generated linkage disequilibrium analysis revealed weak though significant differences in two-locus allelic correlations between naturalized stands and coppice, suggesting that long-term management techniques may influence the genetic makeup of the populations.
Assessing the Genetic Identity of Tuscan Sweet Chestnut (Castanea sativa Mill.)
The sweet chestnut (Castanea sativa Mill.) is an important species of European trees, studied for both ecological and economic reasons. Its cultivation in the Italian peninsula can be linked to the
Chloroplast DNA polymorphism reveals little geographical structure in Castanea sativa Mill. (Fagaceae) throughout southern European countries
The distribution of haplotypic diversity of 38 European chestnut (Castanea sativa Mill.) populations was investigated by PCR/RFLP analysis of regions of the chloroplast and mitochondrial genomes in
Genetic diversity of the sweet chestnut (Castanea sativa Mill.) in Central Europe and the western part of the Balkan Peninsula and evidence of marron genotype introgression into wild populations
TLDR
The results indicate that cultivated-to-wild introgression in the sweet chestnut is dependent on the close proximity of chestnut orchards and naturally occurring populations, and both natural colonization events and significant and lengthy human impact.
Microsatellite markers reveal a strong geographical structure in European populations of Castanea sativa (Fagaceae): evidence for multiple glacial refugia.
TLDR
The inferred population structure shows a strong geographical correspondence with the hypothesized glacial refugia and rules out the migration of the chestnut from Turkey and Greece to Italy.
Insights in the chestnut genetic diversity in Canton Ticino (Southern Switzerland)
TLDR
The genetic germplasm structuring of the analysed chestnut stands is very mild as confirmed by the relatively low level of genetic differentiation and divergence observed among sites, and suggests that three homogeneous gene pools contributed to the formation of the 3 populations sampled.
Mediterranean and Northern Iberian gene pools of wild Castanea sativa Mill. are two differentiated ecotypes originated under natural divergent selection
TLDR
Nine wild Iberian provenances of Castanea sativa Mill were evaluated for several adaptive traits in two provenance–progeny trials with the aim of evaluating the role of natural selection in shaping adaptive variation and increasing the understanding of the genetic structure of this species.
Distribution of genetic variability in populations of two chromosomal races of Dichroplus pratensis (Melanoplinae, Acrididae) and their hybrid zone
TLDR
Differential viability or fertility of hybrids, or asymmetry in mating preferences in favour of one particular cross would cause a higher proportion of matings between hybrid individuals and those from the Southern race, which would explain the high genetic similarity between those groups.
...
...

References

SHOWING 1-10 OF 62 REFERENCES
Evolution of Castanea sativa Mill, in Turkey and Europe
TLDR
No evidence for selection could be found at the large geographical scale of this study, although previous regional works have shown spatial patterns of allelic frequencies at a few loci and phenotypic differentiation consistent with the action of past selective pressures.
Congruence between genetic, morphometric, and physiological data on differentiation of Turkish chestnut (Castanea sativa)
TLDR
Patterns of variability of genetic, morphometric, and physiological traits in Turkish chestnut (Castanea sativa Mill.) reveal remarkably consistent variation patterns for the three types of biological traits.
Genetic differentiation among Turkish chestnut (Castanea sativa Mill.) populations
TLDR
Western Turkish demes seem genetically to be more closely related to Italian populations than to Eastern demes, and most enzymatic polymorphisms show a gradual or sharp difference between Eastern and Western Turkish populations.
GENETIC ANALYSIS OF A HYBRID ZONE BETWEEN THE FIRE‐BELLIED TOADS, BOMBINA BOMBINA AND B. VARIEGATA, NEAR CRACOW IN SOUTHERN POLAND
TLDR
A survey of five diagnostic enzyme loci across the hybrid zone near Cracow in Southern Poland to estimate the dispersal rate, selection pressures, and numbers of loci which maintain this zone suggests that the zone is maintained largely by selection against hybrids.
Estimates of selection and gene flow from measures of cline width and linkage disequilibrium in heliconius hybrid zones.
TLDR
The method applied to hybrid zones between color pattern races in a pair of Peruvian Heliconius butterfly species showed that the genetics and evolution of mimicry are still only sketchily understood.
Genetic analysis of hybrid zones
TLDR
The aim of this chapter is to explain how data on discrete markers and on quantitative traits can be used to estimate parameters of hybrid zones and use computer simulations to show that the estimates do not depend on exactly how selection maintains the differences between the hybridizing populations.
CYCLIC HYBRIDIZATION AS A SURVIVAL MECHANISM IN THE NEW ZEALAND FOREST FLORA
TLDR
An attempt to provide an hypothesis which will serve to explain all (or most) of the peculiarities of the flora in terms of its supposed evolutionary history from early Tertiary times.
The role of hybridization in evolution
TLDR
Fisher’s model of stabilizing selection on multiple traits, under which reproductive isolation evolves as a side‐effect of adaptation in allopatry, confirms a priori arguments that while recombinant hybrids are less fit on average, some gene combinations may be fitter than the parents, even in the parental environment.
Geographic variation, speciation, and clines.
  • J. Endler
  • Medicine
    Monographs in population biology
  • 1977
TLDR
Professor Endler shows how geographic differentiation and speciation may develop in spite of continuous gene flow, and considers the interpretation of natural clines and the associated geographic patterns of subspecies and species.
Problems in Distinguishing Historical from Ecological Factors in Biogeography
TLDR
The Pleistocene forest refuge hypothesis and vicariance biogeography are given; the refuge hypothesis yields three predictions, but only one is upheld-concordance of centers of diversity; the distribution of positions and widths of contact zones is inconsistent with the hypothesis.
...
...