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Efraín Tovar-sánchez - One of the best experts on this subject based on the ideXlab platform.
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Hybridization of Quercus Castanea (Fagaceae) across a red oak species gradient in Mexico
Plant Systematics and Evolution, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Elgar Castillo-mendoza, Guadalupe Rangel-altamirano, Efraín Tovar-sánchezAbstract:Interspecific gene flow between more than two species is a common phenomenon in oaks, which can occur simultaneously among different species, promoting the transfer of genetic material across species boundaries. However, the hybridization dynamics in multispecies hybrid zones remain unknown. In this study, we provide genetic evidence of hybridization and introgression of Quercus Castanea across a natural gradient of red oak species richness. We analyzed five populations recognized morphologically as “pure” Q. Castanea, one allopatric and four sympatric populations, where the number of red oak species associated with Q. Castanea ranged from one to four. Also, one allopatric population of each red oak species that occurs in sympatry with Q. Castanea was chosen as reference population (Q. crassipes, Q. laurina, Q. mexicana and Q. crassifolia). In total, six nSSRs were used in 10 and 20 individuals from each allopatric and sympatric populations, respectively. Our results showed that allopatric populations formed completely distinct genetic clusters. In sympatric populations, we found evidence of hybridization and introgression among Q. Castanea and three of its associated red oak species. However, the occurrence and frequency of hybrids between Q. Castanea and these species varied among stands. Our analyses provide evidence and new insights into hybridization and introgression dynamics within a Mexican red oak species complex, through a focal species, Q. Castanea.
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Effect of a red oak species gradient on genetic structure and diversity of Quercus Castanea (Fagaceae) in Mexico
Tree Genetics & Genomes, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Susana Valencia-Ávalos, Efraín Tovar-sánchezAbstract:Incipient reproductive barriers are a common characteristic of oak species. Disruption of these barriers promotes changes in diversity and genetic structure of the species involved. Quercus Castanea is a red oak with wide geographic distribution in Mexico, which presents atypically high morphological variability when it occurs in sympatry with other red oak species, suggesting that hybridization may explain the observed variation. We tested if the genetic structure and diversity levels of Q. Castanea are related to the number of red oak species growing in sympatry. In total, 14 microsatellite (SSRs) primers (six nSSRs and eight cpSSRs) were used in 120 Q. Castanea individuals (20/site) belonging to six populations, where the number of red oak species associated varied from zero to five. Results showed a positive and significant relationship between the genetic diversity of Q. Castanea and the number of red oak species growing in sympatry, regardless of the marker type or the parameter of genetic diversity analyzed. Also, we found a higher genetic differentiation of Q. Castanea populations using cpSSRs in comparison with nSSRs. Our results suggest that temperate forests with high red oaks species richness co-dominated by Q. Castanea promote the increase in this species genetic diversity. From a conservation perspective, high genetic diversity levels of foundation species such as Q. Castanea may have positive cascade effects extending to other species in the community.
Leticia Valencia-cuevas - One of the best experts on this subject based on the ideXlab platform.
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Hybridization of Quercus Castanea (Fagaceae) across a red oak species gradient in Mexico
Plant Systematics and Evolution, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Elgar Castillo-mendoza, Guadalupe Rangel-altamirano, Efraín Tovar-sánchezAbstract:Interspecific gene flow between more than two species is a common phenomenon in oaks, which can occur simultaneously among different species, promoting the transfer of genetic material across species boundaries. However, the hybridization dynamics in multispecies hybrid zones remain unknown. In this study, we provide genetic evidence of hybridization and introgression of Quercus Castanea across a natural gradient of red oak species richness. We analyzed five populations recognized morphologically as “pure” Q. Castanea, one allopatric and four sympatric populations, where the number of red oak species associated with Q. Castanea ranged from one to four. Also, one allopatric population of each red oak species that occurs in sympatry with Q. Castanea was chosen as reference population (Q. crassipes, Q. laurina, Q. mexicana and Q. crassifolia). In total, six nSSRs were used in 10 and 20 individuals from each allopatric and sympatric populations, respectively. Our results showed that allopatric populations formed completely distinct genetic clusters. In sympatric populations, we found evidence of hybridization and introgression among Q. Castanea and three of its associated red oak species. However, the occurrence and frequency of hybrids between Q. Castanea and these species varied among stands. Our analyses provide evidence and new insights into hybridization and introgression dynamics within a Mexican red oak species complex, through a focal species, Q. Castanea.
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Effect of a red oak species gradient on genetic structure and diversity of Quercus Castanea (Fagaceae) in Mexico
Tree Genetics & Genomes, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Susana Valencia-Ávalos, Efraín Tovar-sánchezAbstract:Incipient reproductive barriers are a common characteristic of oak species. Disruption of these barriers promotes changes in diversity and genetic structure of the species involved. Quercus Castanea is a red oak with wide geographic distribution in Mexico, which presents atypically high morphological variability when it occurs in sympatry with other red oak species, suggesting that hybridization may explain the observed variation. We tested if the genetic structure and diversity levels of Q. Castanea are related to the number of red oak species growing in sympatry. In total, 14 microsatellite (SSRs) primers (six nSSRs and eight cpSSRs) were used in 120 Q. Castanea individuals (20/site) belonging to six populations, where the number of red oak species associated varied from zero to five. Results showed a positive and significant relationship between the genetic diversity of Q. Castanea and the number of red oak species growing in sympatry, regardless of the marker type or the parameter of genetic diversity analyzed. Also, we found a higher genetic differentiation of Q. Castanea populations using cpSSRs in comparison with nSSRs. Our results suggest that temperate forests with high red oaks species richness co-dominated by Q. Castanea promote the increase in this species genetic diversity. From a conservation perspective, high genetic diversity levels of foundation species such as Q. Castanea may have positive cascade effects extending to other species in the community.
J. Fernández-lópez - One of the best experts on this subject based on the ideXlab platform.
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Additive and non-additive genetic parameters for multipurpose traits in a clonally replicated incomplete factorial test of Castanea spp.
Tree Genetics & Genomes, 2016Co-Authors: B. Míguez-soto, A. López-villamor, J. Fernández-lópezAbstract:Second-year traits of growth, stem form, terminal flushing, and survival were assessed in 1770 ramets from 295 clones of 16 full-sib families of Castanea spp. Additive, dominance, and epistatic genetic variances were estimated in a clonally replicated incomplete 5 × 4 factorial test. Parents of the mating design were selected mainly on their phenotypes for wood quality (Castanea sativa traditional varieties) and their proven resistance to Phytophthora spp. (Asiatic species and Castanea crenata × C. sativa hybrids). Additive genetic variances were estimated to be 1.7–9 times greater than the dominance components. Inferred epistatic variance components showed a significant role in controlling growth traits and branch length. Narrow- and broad-sense heritability estimates showed that terminal flushing date was the most heritable trait, followed by height. The high estimates of half-sib, full-sib, and clonal mean heritabilities for almost all traits suggest that different strategies of backwards and forwards selection could be proposed. The ranking of the breeding values of parents allow us to select the best parents for new crosses and extend the mating design. Favorable genetic correlations were found between growth traits and straightness, so multi-trait selection looks promising. Our results provide the first information on the partitioning of genetic variance in Castanea spp. and a starting point for devising new selection strategies.
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Morphological, molecular and statistical tools to identify Castanea species and their hybrids
Conservation Genetics, 2012Co-Authors: J. Fernández-cruz, J. Fernández-lópezAbstract:The aim of this study was to investigate, in relation to reference samples, the genetic structure of several natural Castanea populations of unknown origin and of hybrids from the clone collection of the Lourizan Forest Research Center. A total of 115 individuals sampled from four Castanea sativa stands located in the northwest of Spain, 61 Castanea crenata individuals and 27 Castanea mollissima individuals were classified on the basis of four morphological traits, and genotyped with 11 microsatellite loci to define a set of reference samples. The data analyzed with the program STRUCTURE detected four clusters: the two Asiatic species and two clusters in C. sativa. From these reference samples, pure individuals and hybrids of known genealogy were simulated to determine the efficiency with which STRUCTURE and NEWHYBRIDS assigned them to pure or hybrid groups and to a specific genealogical class, respectively. As expected, the discrimination and assignment of the simulated individuals improved with increasing F st value. The two clusters identified within C. sativa may correspond to gene pools with different adaptive characteristics previously identified in provenance tests; pure and admixed populations of both C. sativa gene pools were identified.
Daniel Piñero - One of the best experts on this subject based on the ideXlab platform.
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Hybridization of Quercus Castanea (Fagaceae) across a red oak species gradient in Mexico
Plant Systematics and Evolution, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Elgar Castillo-mendoza, Guadalupe Rangel-altamirano, Efraín Tovar-sánchezAbstract:Interspecific gene flow between more than two species is a common phenomenon in oaks, which can occur simultaneously among different species, promoting the transfer of genetic material across species boundaries. However, the hybridization dynamics in multispecies hybrid zones remain unknown. In this study, we provide genetic evidence of hybridization and introgression of Quercus Castanea across a natural gradient of red oak species richness. We analyzed five populations recognized morphologically as “pure” Q. Castanea, one allopatric and four sympatric populations, where the number of red oak species associated with Q. Castanea ranged from one to four. Also, one allopatric population of each red oak species that occurs in sympatry with Q. Castanea was chosen as reference population (Q. crassipes, Q. laurina, Q. mexicana and Q. crassifolia). In total, six nSSRs were used in 10 and 20 individuals from each allopatric and sympatric populations, respectively. Our results showed that allopatric populations formed completely distinct genetic clusters. In sympatric populations, we found evidence of hybridization and introgression among Q. Castanea and three of its associated red oak species. However, the occurrence and frequency of hybrids between Q. Castanea and these species varied among stands. Our analyses provide evidence and new insights into hybridization and introgression dynamics within a Mexican red oak species complex, through a focal species, Q. Castanea.
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Effect of a red oak species gradient on genetic structure and diversity of Quercus Castanea (Fagaceae) in Mexico
Tree Genetics & Genomes, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Susana Valencia-Ávalos, Efraín Tovar-sánchezAbstract:Incipient reproductive barriers are a common characteristic of oak species. Disruption of these barriers promotes changes in diversity and genetic structure of the species involved. Quercus Castanea is a red oak with wide geographic distribution in Mexico, which presents atypically high morphological variability when it occurs in sympatry with other red oak species, suggesting that hybridization may explain the observed variation. We tested if the genetic structure and diversity levels of Q. Castanea are related to the number of red oak species growing in sympatry. In total, 14 microsatellite (SSRs) primers (six nSSRs and eight cpSSRs) were used in 120 Q. Castanea individuals (20/site) belonging to six populations, where the number of red oak species associated varied from zero to five. Results showed a positive and significant relationship between the genetic diversity of Q. Castanea and the number of red oak species growing in sympatry, regardless of the marker type or the parameter of genetic diversity analyzed. Also, we found a higher genetic differentiation of Q. Castanea populations using cpSSRs in comparison with nSSRs. Our results suggest that temperate forests with high red oaks species richness co-dominated by Q. Castanea promote the increase in this species genetic diversity. From a conservation perspective, high genetic diversity levels of foundation species such as Q. Castanea may have positive cascade effects extending to other species in the community.
Patricia Mussali-galante - One of the best experts on this subject based on the ideXlab platform.
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Hybridization of Quercus Castanea (Fagaceae) across a red oak species gradient in Mexico
Plant Systematics and Evolution, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Elgar Castillo-mendoza, Guadalupe Rangel-altamirano, Efraín Tovar-sánchezAbstract:Interspecific gene flow between more than two species is a common phenomenon in oaks, which can occur simultaneously among different species, promoting the transfer of genetic material across species boundaries. However, the hybridization dynamics in multispecies hybrid zones remain unknown. In this study, we provide genetic evidence of hybridization and introgression of Quercus Castanea across a natural gradient of red oak species richness. We analyzed five populations recognized morphologically as “pure” Q. Castanea, one allopatric and four sympatric populations, where the number of red oak species associated with Q. Castanea ranged from one to four. Also, one allopatric population of each red oak species that occurs in sympatry with Q. Castanea was chosen as reference population (Q. crassipes, Q. laurina, Q. mexicana and Q. crassifolia). In total, six nSSRs were used in 10 and 20 individuals from each allopatric and sympatric populations, respectively. Our results showed that allopatric populations formed completely distinct genetic clusters. In sympatric populations, we found evidence of hybridization and introgression among Q. Castanea and three of its associated red oak species. However, the occurrence and frequency of hybrids between Q. Castanea and these species varied among stands. Our analyses provide evidence and new insights into hybridization and introgression dynamics within a Mexican red oak species complex, through a focal species, Q. Castanea.
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Effect of a red oak species gradient on genetic structure and diversity of Quercus Castanea (Fagaceae) in Mexico
Tree Genetics & Genomes, 2014Co-Authors: Leticia Valencia-cuevas, Daniel Piñero, Patricia Mussali-galante, Susana Valencia-Ávalos, Efraín Tovar-sánchezAbstract:Incipient reproductive barriers are a common characteristic of oak species. Disruption of these barriers promotes changes in diversity and genetic structure of the species involved. Quercus Castanea is a red oak with wide geographic distribution in Mexico, which presents atypically high morphological variability when it occurs in sympatry with other red oak species, suggesting that hybridization may explain the observed variation. We tested if the genetic structure and diversity levels of Q. Castanea are related to the number of red oak species growing in sympatry. In total, 14 microsatellite (SSRs) primers (six nSSRs and eight cpSSRs) were used in 120 Q. Castanea individuals (20/site) belonging to six populations, where the number of red oak species associated varied from zero to five. Results showed a positive and significant relationship between the genetic diversity of Q. Castanea and the number of red oak species growing in sympatry, regardless of the marker type or the parameter of genetic diversity analyzed. Also, we found a higher genetic differentiation of Q. Castanea populations using cpSSRs in comparison with nSSRs. Our results suggest that temperate forests with high red oaks species richness co-dominated by Q. Castanea promote the increase in this species genetic diversity. From a conservation perspective, high genetic diversity levels of foundation species such as Q. Castanea may have positive cascade effects extending to other species in the community.