The Experts below are selected from a list of 31599 Experts worldwide ranked by ideXlab platform
Franz Terrazas - One of the best experts on this subject based on the ideXlab platform.
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origins of domestication and Polyploidy in oca oxalis tuberosa oxalidaceae 3 aflp data of oca and four wild tuber bearing taxa
American Journal of Botany, 2009Co-Authors: Eve Emshwiller, Terra J. Theim, Alfredo Grau, Victor Nina, Franz TerrazasAbstract:Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of Polyploidy. To complement other studies of the origins of Polyploidy of the octoploid tuber crop oca (Oxalis tube rosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of do mestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. pic chensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca's progenitor.
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Origins of domestication and Polyploidy in oca (Oxalis tuberosa; Oxalidaceae). 3. AFLP data of oca and four wild, tuber‐bearing taxa
American Journal of Botany, 2009Co-Authors: Eve Emshwiller, Terra J. Theim, Alfredo Grau, Victor Nina, Franz TerrazasAbstract:Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of Polyploidy. To complement other studies of the origins of Polyploidy of the octoploid tuber crop oca (Oxalis tube rosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of do mestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. pic chensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca's progenitor.
Pamela S. Soltis - One of the best experts on this subject based on the ideXlab platform.
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Polyploidy: Pitfalls and paths to a paradigm.
American journal of botany, 2016Co-Authors: Douglas E. Soltis, Clayton J. Visger, D. Blaine Marchant, Pamela S. SoltisAbstract:Investigators have long searched for a Polyploidy paradigm-rules or principles that might be common following polyploidization (whole-genome duplication, WGD). Here we attempt to integrate what is known across the more thoroughly investigated polyploid systems on topics ranging from genetics to ecology. We found that while certain rules may govern gene retention and loss, systems vary in the prevalence of gene silencing vs. homeolog loss, chromosomal change, the presence of a dominant genome (in allopolyploids), and the relative importance of hybridization vs. genome doubling per se. In some lineages, aspects of polyploidization are repeated across multiple origins, but in other species multiple origins behave more stochastically in terms of genetic and phenotypic change. Our investigation also reveals that the path to synthesis is hindered by numerous gaps in our knowledge of even the best-known systems. Particularly concerning is the absence of linkage between genotype and phenotype. Moreover, most recent studies have focused on the genetic and genomic attributes of Polyploidy, but rarely is there an ecological or physiological context. To promote a path to a Polyploidy paradigm (or paradigms), we propose a major community goal over the next 10-20 yr to fill the gaps in our knowledge of well-studied polyploids. Before a meaningful synthesis is possible, more complete data sets are needed for comparison-systems that include comparable genetic, genomic, chromosomal, proteomic, as well as morphological, physiological, and ecological data. Also needed are more natural evolutionary model systems, as most of what we know about Polyploidy continues to come from a few crop and genetic models, systems that often lack the ecological context inherent in natural systems and necessary for understanding the drivers of biodiversity.
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Polyploidy and the proteome
Biochimica et biophysica acta, 2016Co-Authors: Douglas E. Soltis, Biswapriya B. Misra, Shengchen Shan, Sixue Chen, Pamela S. SoltisAbstract:Although major advances have been made during the past 20 years in our understanding of the genetic and genomic consequences of Polyploidy, our knowledge of Polyploidy and the proteome is in its infancy. One of our goals is to stimulate additional study, particularly broad-scale proteomic analyses of polyploids and their progenitors. Although it may be too early to generalize regarding the extent to which transcriptomic data are predictive of the proteome of polyploids, it is clear that the proteome does not always reflect the transcriptome. Despite limited data, important observations on the proteomes of polyploids are emerging. In some cases, proteomic profiles show qualitatively and/or quantitatively non-additive patterns, and proteomic novelty has been observed. Allopolyploids generally combine the parental contributions, but there is evidence of parental dominance of one contributing genome in some allopolyploids. Autopolyploids are typically qualitatively identical to but quantitatively different from their parents. There is also evidence of parental legacy at the proteomic level. Proteomes clearly provide insights into the consequences of genomic merger and doubling beyond what is obtained from genomic and/or transcriptomic data. Translating proteomic changes in polyploids to differences in morphology and physiology remains the holy grail of Polyploidy--this daunting task of linking genotype to proteome to phenotype should emerge as a focus of Polyploidy research in the next decade. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.
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Polyploidy and the proteome Proteins and proteomics
Biochimica et Biophysica Acta, 2016Co-Authors: Douglas E. Soltis, Biswapriya B. Misra, Shengchen Shan, Sixue Chen, Pamela S. SoltisAbstract:Although major advances have been made during the past 20years in our understanding of the genetic and genomic consequences of Polyploidy, our knowledge of Polyploidy and the proteome is in its infancy. One of our goals is to stimulate additional study, particularly broad-scale proteomic analyses of polyploids and their progenitors. Although it may be too early to generalize regarding the extent to which transcriptomic data are predictive of the proteome of polyploids, it is clear that the proteome does not always reflect the transcriptome. Despite limited data, important observations on the proteomes of polyploids are emerging. In some cases, proteomic profiles show qualitatively and/or quantitatively non-additive patterns, and proteomic novelty has been observed. Allopolyploids generally combine the parental contributions, but there is evidence of parental dominance of one contributing genome in some allopolyploids. Autopolyploids are typically qualitatively identical to but quantitatively different from their parents. There is also evidence of parental legacy at the proteomic level. Proteomes clearly provide insights into the consequences of genomic merger and doubling beyond what is obtained from genomic and/or transcriptomic data. Translating proteomic changes in polyploids to differences in morphology and physiology remains the holy grail of Polyploidy — this daunting task of linking genotype to proteome to phenotype should emerge as a focus of Polyploidy research in the next decade. This article is part of a Special Issue entitled: Plant Proteomics— a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.
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Polyploidy and genome evolution in plants
Current Opinion in Genetics & Development, 2015Co-Authors: Blaine D Marchant, Pamela S. Soltis, Yves Van De Peer, Douglas E. SoltisAbstract:Plant genomes vary in size and complexity, fueled in part by processes of whole-genome duplication (WGD; Polyploidy) and subsequent genome evolution. Despite repeated episodes of WGD throughout the evolutionary history of angiosperms in particular, the genomes are not uniformly large, and even plants with very small genomes carry the signatures of ancient duplication events. The processes governing the evolution of plant genomes following these ancient events are largely unknown. Here, we consider mechanisms of diploidization, evidence of genome reorganization in recently formed polyploid species, and macroevolutionary patterns of WGD in plant genomes and propose that the ongoing genomic changes observed in recent polyploids may illustrate the diploidization processes that result in ancient signatures of WGD over geological timescales.
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cytogeography of the humifusa clade of opuntia s s mill 1754 cactaceae opuntioideae opuntieae correlations with pleistocene refugia and morphological traits in a polyploid complex
Comparative Cytogenetics, 2012Co-Authors: Lucas C Majure, Pamela S. Soltis, Walter S Judd, Douglas E. SoltisAbstract:Ploidy has been well studied and used extensively in the genus Opuntia to determine species boundaries, detect evidence of hybridization, and infer evolutionary patterns. We carried out chromosome counts for all members of the Humifusa clade to ascertain whether geographic patterns are associated with differences in ploidy. We then related chromosomal data to observed morphological variability, polyploid formation, and consequently the evolutionary history of the clade. We counted chromosomes of 277 individuals from throughout the ranges of taxa included within the Humifusa clade, with emphasis placed on the widely distributed species, Opuntia humifusa (Raf.) Raf., 1820 s.l. and Opuntia macrorhiza Engelm., 1850 s.l. We also compiled previous counts made for species in the clade along with our new counts to plot geographic distributions of the polyploid and diploid taxa. A phylogeny using nuclear ribosomal ITS sequence data was reconstructed to determine whether ploidal variation is consistent with cladogenesis. We discovered that diploids of the Humifusa clade are restricted to the southeastern United States (U.S.), eastern Texas, and southeastern New Mexico. Polyploid members of the clade, however, are much more widely distributed, occurring as far north as the upper midwestern U.S. (e.g., Michigan, Minnesota, Wisconsin). Morphological differentiation, although sometimes cryptic, is commonly observed among diploid and polyploid cytotypes, and such morphological distinctions may be useful in diagnosing possible cryptic species. Certain polyploid populations of Opuntia humifusa s.l. and Opuntia macrorhiza s.l., however, exhibit introgressive morphological characters, complicating species delineations. Phylogenetically, the Humifusa clade forms two subclades that are distributed, respectively, in the southeastern U.S. (including all southeastern U.S. diploids, polyploid Opuntia abjecta Small, 1923, and polyploid Opuntia pusilla (Haw.) Haw., 1812) and the southwestern U.S. (including all southwestern U.S. diploids and polyploids). In addition, tetraploid Opuntia humifusa s.l., which occurs primarily in the eastern U.S., is resolved in the southwestern diploid clade instead of with the southeastern diploid clade that includes diploid Opuntia humifusa s.l. Our results not only provide evidence for the polyphyletic nature of Opuntia humifusa and Opuntia macrorhiza, suggesting that each of these represents more than one species, but also demonstrate the high frequency of Polyploidy in the Humifusa clade and the major role that genome duplication has played in the diversification of this lineage of Opuntia s.s. Our data also suggest that the southeastern and southwestern U.S. may represent glacial refugia for diploid members of this clade and that the clade as a whole should be considered a mature polyploid species complex. Widespread polyploids are likely derivatives of secondary contact among southeastern and southwestern diploid taxa as a result of the expansion and contraction of suitable habitat during the Pleistocene following glacial and interglacial events.
Eve Emshwiller - One of the best experts on this subject based on the ideXlab platform.
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origins of domestication and Polyploidy in oca oxalis tuberosa oxalidaceae 3 aflp data of oca and four wild tuber bearing taxa
American Journal of Botany, 2009Co-Authors: Eve Emshwiller, Terra J. Theim, Alfredo Grau, Victor Nina, Franz TerrazasAbstract:Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of Polyploidy. To complement other studies of the origins of Polyploidy of the octoploid tuber crop oca (Oxalis tube rosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of do mestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. pic chensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca's progenitor.
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Origins of domestication and Polyploidy in oca (Oxalis tuberosa; Oxalidaceae). 3. AFLP data of oca and four wild, tuber‐bearing taxa
American Journal of Botany, 2009Co-Authors: Eve Emshwiller, Terra J. Theim, Alfredo Grau, Victor Nina, Franz TerrazasAbstract:Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of Polyploidy. To complement other studies of the origins of Polyploidy of the octoploid tuber crop oca (Oxalis tube rosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of do mestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. pic chensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca's progenitor.
Douglas E. Soltis - One of the best experts on this subject based on the ideXlab platform.
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Polyploidy: Pitfalls and paths to a paradigm.
American journal of botany, 2016Co-Authors: Douglas E. Soltis, Clayton J. Visger, D. Blaine Marchant, Pamela S. SoltisAbstract:Investigators have long searched for a Polyploidy paradigm-rules or principles that might be common following polyploidization (whole-genome duplication, WGD). Here we attempt to integrate what is known across the more thoroughly investigated polyploid systems on topics ranging from genetics to ecology. We found that while certain rules may govern gene retention and loss, systems vary in the prevalence of gene silencing vs. homeolog loss, chromosomal change, the presence of a dominant genome (in allopolyploids), and the relative importance of hybridization vs. genome doubling per se. In some lineages, aspects of polyploidization are repeated across multiple origins, but in other species multiple origins behave more stochastically in terms of genetic and phenotypic change. Our investigation also reveals that the path to synthesis is hindered by numerous gaps in our knowledge of even the best-known systems. Particularly concerning is the absence of linkage between genotype and phenotype. Moreover, most recent studies have focused on the genetic and genomic attributes of Polyploidy, but rarely is there an ecological or physiological context. To promote a path to a Polyploidy paradigm (or paradigms), we propose a major community goal over the next 10-20 yr to fill the gaps in our knowledge of well-studied polyploids. Before a meaningful synthesis is possible, more complete data sets are needed for comparison-systems that include comparable genetic, genomic, chromosomal, proteomic, as well as morphological, physiological, and ecological data. Also needed are more natural evolutionary model systems, as most of what we know about Polyploidy continues to come from a few crop and genetic models, systems that often lack the ecological context inherent in natural systems and necessary for understanding the drivers of biodiversity.
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Polyploidy and the proteome
Biochimica et biophysica acta, 2016Co-Authors: Douglas E. Soltis, Biswapriya B. Misra, Shengchen Shan, Sixue Chen, Pamela S. SoltisAbstract:Although major advances have been made during the past 20 years in our understanding of the genetic and genomic consequences of Polyploidy, our knowledge of Polyploidy and the proteome is in its infancy. One of our goals is to stimulate additional study, particularly broad-scale proteomic analyses of polyploids and their progenitors. Although it may be too early to generalize regarding the extent to which transcriptomic data are predictive of the proteome of polyploids, it is clear that the proteome does not always reflect the transcriptome. Despite limited data, important observations on the proteomes of polyploids are emerging. In some cases, proteomic profiles show qualitatively and/or quantitatively non-additive patterns, and proteomic novelty has been observed. Allopolyploids generally combine the parental contributions, but there is evidence of parental dominance of one contributing genome in some allopolyploids. Autopolyploids are typically qualitatively identical to but quantitatively different from their parents. There is also evidence of parental legacy at the proteomic level. Proteomes clearly provide insights into the consequences of genomic merger and doubling beyond what is obtained from genomic and/or transcriptomic data. Translating proteomic changes in polyploids to differences in morphology and physiology remains the holy grail of Polyploidy--this daunting task of linking genotype to proteome to phenotype should emerge as a focus of Polyploidy research in the next decade. This article is part of a Special Issue entitled: Plant Proteomics--a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.
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Polyploidy and the proteome Proteins and proteomics
Biochimica et Biophysica Acta, 2016Co-Authors: Douglas E. Soltis, Biswapriya B. Misra, Shengchen Shan, Sixue Chen, Pamela S. SoltisAbstract:Although major advances have been made during the past 20years in our understanding of the genetic and genomic consequences of Polyploidy, our knowledge of Polyploidy and the proteome is in its infancy. One of our goals is to stimulate additional study, particularly broad-scale proteomic analyses of polyploids and their progenitors. Although it may be too early to generalize regarding the extent to which transcriptomic data are predictive of the proteome of polyploids, it is clear that the proteome does not always reflect the transcriptome. Despite limited data, important observations on the proteomes of polyploids are emerging. In some cases, proteomic profiles show qualitatively and/or quantitatively non-additive patterns, and proteomic novelty has been observed. Allopolyploids generally combine the parental contributions, but there is evidence of parental dominance of one contributing genome in some allopolyploids. Autopolyploids are typically qualitatively identical to but quantitatively different from their parents. There is also evidence of parental legacy at the proteomic level. Proteomes clearly provide insights into the consequences of genomic merger and doubling beyond what is obtained from genomic and/or transcriptomic data. Translating proteomic changes in polyploids to differences in morphology and physiology remains the holy grail of Polyploidy — this daunting task of linking genotype to proteome to phenotype should emerge as a focus of Polyploidy research in the next decade. This article is part of a Special Issue entitled: Plant Proteomics— a bridge between fundamental processes and crop production, edited by Dr. Hans-Peter Mock.
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Polyploidy and genome evolution in plants
Current Opinion in Genetics & Development, 2015Co-Authors: Blaine D Marchant, Pamela S. Soltis, Yves Van De Peer, Douglas E. SoltisAbstract:Plant genomes vary in size and complexity, fueled in part by processes of whole-genome duplication (WGD; Polyploidy) and subsequent genome evolution. Despite repeated episodes of WGD throughout the evolutionary history of angiosperms in particular, the genomes are not uniformly large, and even plants with very small genomes carry the signatures of ancient duplication events. The processes governing the evolution of plant genomes following these ancient events are largely unknown. Here, we consider mechanisms of diploidization, evidence of genome reorganization in recently formed polyploid species, and macroevolutionary patterns of WGD in plant genomes and propose that the ongoing genomic changes observed in recent polyploids may illustrate the diploidization processes that result in ancient signatures of WGD over geological timescales.
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cytogeography of the humifusa clade of opuntia s s mill 1754 cactaceae opuntioideae opuntieae correlations with pleistocene refugia and morphological traits in a polyploid complex
Comparative Cytogenetics, 2012Co-Authors: Lucas C Majure, Pamela S. Soltis, Walter S Judd, Douglas E. SoltisAbstract:Ploidy has been well studied and used extensively in the genus Opuntia to determine species boundaries, detect evidence of hybridization, and infer evolutionary patterns. We carried out chromosome counts for all members of the Humifusa clade to ascertain whether geographic patterns are associated with differences in ploidy. We then related chromosomal data to observed morphological variability, polyploid formation, and consequently the evolutionary history of the clade. We counted chromosomes of 277 individuals from throughout the ranges of taxa included within the Humifusa clade, with emphasis placed on the widely distributed species, Opuntia humifusa (Raf.) Raf., 1820 s.l. and Opuntia macrorhiza Engelm., 1850 s.l. We also compiled previous counts made for species in the clade along with our new counts to plot geographic distributions of the polyploid and diploid taxa. A phylogeny using nuclear ribosomal ITS sequence data was reconstructed to determine whether ploidal variation is consistent with cladogenesis. We discovered that diploids of the Humifusa clade are restricted to the southeastern United States (U.S.), eastern Texas, and southeastern New Mexico. Polyploid members of the clade, however, are much more widely distributed, occurring as far north as the upper midwestern U.S. (e.g., Michigan, Minnesota, Wisconsin). Morphological differentiation, although sometimes cryptic, is commonly observed among diploid and polyploid cytotypes, and such morphological distinctions may be useful in diagnosing possible cryptic species. Certain polyploid populations of Opuntia humifusa s.l. and Opuntia macrorhiza s.l., however, exhibit introgressive morphological characters, complicating species delineations. Phylogenetically, the Humifusa clade forms two subclades that are distributed, respectively, in the southeastern U.S. (including all southeastern U.S. diploids, polyploid Opuntia abjecta Small, 1923, and polyploid Opuntia pusilla (Haw.) Haw., 1812) and the southwestern U.S. (including all southwestern U.S. diploids and polyploids). In addition, tetraploid Opuntia humifusa s.l., which occurs primarily in the eastern U.S., is resolved in the southwestern diploid clade instead of with the southeastern diploid clade that includes diploid Opuntia humifusa s.l. Our results not only provide evidence for the polyphyletic nature of Opuntia humifusa and Opuntia macrorhiza, suggesting that each of these represents more than one species, but also demonstrate the high frequency of Polyploidy in the Humifusa clade and the major role that genome duplication has played in the diversification of this lineage of Opuntia s.s. Our data also suggest that the southeastern and southwestern U.S. may represent glacial refugia for diploid members of this clade and that the clade as a whole should be considered a mature polyploid species complex. Widespread polyploids are likely derivatives of secondary contact among southeastern and southwestern diploid taxa as a result of the expansion and contraction of suitable habitat during the Pleistocene following glacial and interglacial events.
Terra J. Theim - One of the best experts on this subject based on the ideXlab platform.
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origins of domestication and Polyploidy in oca oxalis tuberosa oxalidaceae 3 aflp data of oca and four wild tuber bearing taxa
American Journal of Botany, 2009Co-Authors: Eve Emshwiller, Terra J. Theim, Alfredo Grau, Victor Nina, Franz TerrazasAbstract:Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of Polyploidy. To complement other studies of the origins of Polyploidy of the octoploid tuber crop oca (Oxalis tube rosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of do mestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. pic chensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca's progenitor.
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Origins of domestication and Polyploidy in oca (Oxalis tuberosa; Oxalidaceae). 3. AFLP data of oca and four wild, tuber‐bearing taxa
American Journal of Botany, 2009Co-Authors: Eve Emshwiller, Terra J. Theim, Alfredo Grau, Victor Nina, Franz TerrazasAbstract:Many crops are polyploids, and it can be challenging to untangle the often complicated history of their origins of domestication and origins of Polyploidy. To complement other studies of the origins of Polyploidy of the octoploid tuber crop oca (Oxalis tube rosa) that used DNA sequence data and phylogenetic methods, we here compared AFLP data for oca with four wild, tuber-bearing Oxalis taxa found in different regions of the central Andes. Results confirmed the divergence of two use-categories of cultivated oca that indigenous farmers use for different purposes, suggesting the possibility that they might have had separate origins of do mestication. Despite previous results with nuclear-encoded, chloroplast-expressed glutamine synthetase suggesting that O. pic chensis might be a progenitor of oca, AFLP data of this species, as well as different populations of wild, tuber-bearing Oxalis found in Lima Department, Peru, were relatively divergent from O. tuberosa. Results from all analytical methods suggested that the unnamed wild, tuber-bearing Oxalis found in Bolivia and O. chicligastensis in NW Argentina are the best candidates as the genome donors for polyploid O. tuberosa, but the results were somewhat equivocal about which of these two taxa is the more strongly supported as oca's progenitor.
