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Castiblanco-Álvarez Felipe - One of the best experts on this subject based on the ideXlab platform.
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Control de pastos exóticos mediante sombreado artificial y reubicación de especies nativas como estrategias para la restauración ecológica del páramo andino (PNN Chingaza-Colombia)
2012Co-Authors: Castiblanco-Álvarez FelipeAbstract:En un pastizal de páramo andino, atmosféricamente húmedo, dominado por pastos exóticos (Anthoxanthum odoratum, Holcus lanatus), se evaluaron tres estrategias: i) sombreado artificial con acolchado de plástico negro durante tres o siete meses, con el fin de controlar la regeneración de los pastos exóticos, luego de la remoción de la biomasa epigea y parte de la hipogea; ii) reubicación de especies: dos arbustos (Arcytophyllum nitidum, Pentacalia ledifolia) y dos rosetas (Paepalanthus alpinus, Puya trianae), para la conformación de núcleos de restauración, en las parcelas donde se había realizado la remoción de pastos; iii) sombreado artificial sobre la reubicación de especies. Se registró la cobertura (pastos, especies); la altura, la supervivencia (especies); y el número de hojas (rosetas). La cobertura de pastos exóticos fue mayor en el control, respecto al sombreado durante tres o siete meses (p
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Control de pastos exóticos mediante sombreado artificial y reubicación de especies nativas como estrategias para la restauración ecológica del páramo andino (PNN Chingaza-Colombia)
2012Co-Authors: Castiblanco-Álvarez FelipeAbstract:En un pastizal de páramo andino, atmosféricamente húmedo, dominado por pastos exóticos (Anthoxanthum odoratum, Holcus lanatus), se evaluaron tres estrategias: i) sombreado artificial con acolchado de plástico negro durante tres o siete meses, con el fin de controlar la regeneración de los pastos exóticos, luego de la remoción de la biomasa epigea y parte de la hipogea; ii) reubicación de especies: dos arbustos (Arcytophyllum nitidum, Pentacalia ledifolia) y dos rosetas (Paepalanthus alpinus, Puya trianae), para la conformación de núcleos de restauración, en las parcelas donde se había realizado la remoción de pastos; iii) sombreado artificial sobre la reubicación de especies. Se registró la cobertura (pastos, especies); la altura, la supervivencia (especies); y el número de hojas (rosetas). La cobertura de pastos exóticos fue mayor en el control, respecto al sombreado durante tres o siete meses (p0,001). Ante la ausencia de luz solar, la cobertura de pastos fue siempre la más baja (0,283-0,820%), en el tratamiento con sombreado artificial durante siete meses, por lo que este tratamiento se recomienda para el control de la regeneración de los pastos exóticos. El número de hojas disminuyó en Puya trianae, luego de 2,7 meses de la reubicación, quizá por el estrés generado en el desarrollo de la estrategia, por lo que no se recomienda esta especie en la conformación de núcleos de restauración. En las demás especies reubicadas se recomienda continuar el monitoreo para evaluar su efectividad en la estrategia de reubicación y el efecto del sombreado artificial sobre éstas.In Andean páramo grassland, wet atmospherically, dominated by exotic grasses (Anthoxanthum odoratum, Holcus lanatus), we evaluated three strategies: i) artificial shading with black plastic mulch for three or seven months and control, to control the regeneration of exotic grasses, after removal epigeal biomass and part of the hypogean biomass; ii) relocation of species: two shrubs (Arcytophyllum nitidum, Pentacalia ledifolia) and two rosettes (Paepalanthus alpinus, Puya trianae), for the formation of nuclei of restoration, in plots where there had been grass removal; iii) artificial shading on the relocation of species. We recorded the coverage (grasses, species); the height, the survival (species) and the number of leaves (rosette). Exotic grass cover was greater in the control, with respect to shading for three to seven months (p 0.001). In the absence of sunlight, the grass cover was always lower (0.283-0.820%), in artificial shading treatment for seven months, so that this treatment is recommended for the regeneration control of exotic grasses. The number of leaves decreased in Puya trianae, 2.7 months after the relocation, perhaps by stress generated in the development of the strategy, so this species is not recommended in shaping nuclei restoration. In other species relocated is recommended to continue monitoring to assess its effectiveness in relocation strategy and effect of artificial shading on them.Pregrad
Pavel Trávníček - One of the best experts on this subject based on the ideXlab platform.
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On the Origin of Tetraploid Vernal Grasses (Anthoxanthum) in Europe
'MDPI AG', 2021Co-Authors: Zuzana Chumová, Terezie Mandáková, Pavel TrávníčekAbstract:Polyploidy has played a crucial role in the evolution of many plant taxa, namely in higher latitudinal zones. Surprisingly, after several decades of an intensive research on polyploids, there are still common polyploid species whose evolutionary history is virtually unknown. Here, we addressed the origin of sweet vernal grass (Anthoxanthum odoratum) using flow cytometry, DNA sequencing, and in situ hybridization-based cytogenetic techniques. An allotetraploid and polytopic origin of the species has been verified. The chromosome study reveals an extensive variation between the European populations. In contrast, an autopolyploid origin of the rarer tetraploid vernal grass species, A. alpinum, has been corroborated. Diploid A. alpinum played an essential role in the polyploidization of both European tetraploids studied
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RESEARCH ARTICLE Evolutionary and Taxonomic Implications of Variation in Nuclear Genome Size: Lesson from the Grass Genus Anthoxanthum (Poaceae)
2016Co-Authors: Zuzana Chumová, Jana Krejčíková, Jan Suda, Terezie M, Pavel TrávníčekAbstract:The genus Anthoxanthum (sweet vernal grass, Poaceae) represents a taxonomically intri-cate polyploid complex with large phenotypic variation and its evolutionary relationships still poorly resolved. In order to get insight into the geographic distribution of ploidy levels and assess the taxonomic value of genome size data, we determined C- and Cx-values in 628 plants representing all currently recognized European species collected from 197 popula-tions in 29 European countries. The flow cytometric estimates were supplemented by con-ventional chromosome counts. In addition to diploids, we found two low (rare 3x and common 4x) and one high (~16x– 18x) polyploid levels. Mean holoploid genome sizes ranged from 5.52 pg in diploid A. alpinum to 44.75 pg in highly polyploid A. amarum, while the size of monoploid genomes ranged from 2.75 pg in tetraploid A. alpinum to 9.19 pg in diploid A. gracile. In contrast to Central and Northern Europe, which harboured only limited cytological variation, a much more complex pattern of genome sizes was revealed in the Mediterranean, particularly in Corsica. Eight taxonomic groups that partly corresponded to traditionally recognized spe
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Evolutionary and Taxonomic Implications of Variation in Nuclear Genome Size: Lesson from the Grass Genus Anthoxanthum (Poaceae)
2015Co-Authors: Zuzana Chumová, Jana Krejčíková, Terezie Mandáková, Jan Suda, Pavel TrávníčekAbstract:The genus Anthoxanthum (sweet vernal grass, Poaceae) represents a taxonomically intricate polyploid complex with large phenotypic variation and its evolutionary relationships still poorly resolved. In order to get insight into the geographic distribution of ploidy levels and assess the taxonomic value of genome size data, we determined C- and Cx-values in 628 plants representing all currently recognized European species collected from 197 populations in 29 European countries. The flow cytometric estimates were supplemented by conventional chromosome counts.In addition to diploids, we found two low (rare 3x and common 4x) and one high (~16x–18x) polyploid levels. Mean holoploid genome sizes ranged from 5.52 pg in diploid A. alpinum to 44.75 pg in highly polyploid A. amarum, while the size of monoploid genomes ranged from 2.75 pg in tetraploid A. alpinum to 9.19 pg in diploid A. gracile. In contrast to Central and Northern Europe, which harboured only limited cytological variation, a much more complex pattern of genome sizes was revealed in the Mediterranean, particularly in Corsica. Eight taxonomic groups that partly corresponded to traditionally recognized species were delimited based on genome size values and phenotypic variation. Whereas our data supported the merger of A. aristatum and A. ovatum, eastern Mediterranean populations traditionally referred to as diploid A. odoratum were shown to be cytologically distinct, and may represent a new taxon. Autopolyploid origin was suggested for 4x A. alpinum. In contrast, 4x A. odoratum seems to be an allopolyploid, based on the amounts of nuclear DNA. Intraspecific variation in genome size was observed in all recognized species, the most striking example being the A. aristatum/ovatum complex.Altogether, our study showed that genome size can be a useful taxonomic marker in Anthoxathum to not only guide taxonomic decisions but also help resolve evolutionary relationships in this challenging grass genus.
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Distribution of species and cytotypes of Anthoxanthum in the area studied, based on analysis of 628 individuals from 197 populations sampled in 29 European countries.
2015Co-Authors: Zuzana Chumová, Jana Krejčíková, Terezie Mandáková, Jan Suda, Pavel TrávníčekAbstract:Distribution of species and cytotypes of Anthoxanthum in the area studied, based on analysis of 628 individuals from 197 populations sampled in 29 European countries.
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Box-and-whisker plots showing holoploid genome sizes (2C-values) for eight groups representing different species and cytotypes of Anthoxanthum.
2015Co-Authors: Zuzana Chumová, Jana Krejčíková, Terezie Mandáková, Jan Suda, Pavel TrávníčekAbstract:(A) (ploidy categories are marked as “2x”–diploids, “4x”–tetraploids and “poly”–high polyploid). (B) Box-and-whisker plots showing monoploid genome sizes (1Cx-values) for six groups representing different species and cytotypes of Anthoxanthum (Cx-values in the high-polyploid A. amarum and the A. aristatum/ovatum complex could not be calculated due to uncertain ploidy levels).
Manuel Pimentel - One of the best experts on this subject based on the ideXlab platform.
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DNA and AFLP matrices used in the paper "Sweet vernal grasses (Anthoxanthum) colonized African mountains along two fronts in the Late Pliocene, followed by secondary contact, polyploidization and local extinction in the Pleistocene", accepted for publication in Molecular Ecology
2017Co-Authors: Manuel PimentelAbstract:Concatenated DNA (nuclear; ITS and ETS and plastid, trnLF and trnTL) and AFLP matrices used in the paper "Sweet vernal grasses (Anthoxanthum) colonized African mountains along two fronts in the Late Pliocene, followed by secondary contact, polyploidization and local extinction in the Pleistocene" by Felly Mugizi Tusiime, Abel Gizaw, Tigist Wondimu, Catherine Aloyce Masao, Ahmed Abdikadir Abdi, Vincent Muwanika, Pavel Trávníček, Sileshi Nemomissa, Magnus Popp, Gerald Eilu, Christian Brochmann and Manuel Pimentel, accepted for publication in Molecular Ecology
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Relationships between the close congeners Anthoxanthum odoratum and A. alpinum (Poaceae, Pooideae) assessed by morphological and molecular methods
Botanical Journal of the Linnean Society, 2008Co-Authors: Manuel Pimentel, Elvira SahuquilloAbstract:Anthoxanthum alpinum Love & Love has been described as a diploid perennial distributed in northern Eurasia and the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid Anthoxanthum odoratum L. have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to use different approaches to assess the relationships between close congeners, such as the pair A. odoratum/A. alpinum. Macromorphological, micromorphological, and molecular data were gathered and analysed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Different cluster analyses were performed to study the relatedness between individuals and populations. Subsequently, a principal components analysis was computed on the basis of macromorphological quantitative traits, and principal coordinates analysis was used to analyse qualitative, micromorphological, and random amplification of polymorphic DNA (RAPD) data. An analysis of molecular variance was applied to the molecular data, and the genetic differentiation between samples was measured using the FST estimator. The results showed that the geographical origin was more important than the ploidy level in explaining the relatedness between specimens and populations. Moreover, a strong correlation was found between the micromorphological traits and environmental parameters. The results of the analyses do not support the assignment of a specific taxonomic rank to A. alpinum. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 156, 237–252.
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relationships among some populations of Anthoxanthum alpinum and a odoratum poaceae pooideae a morphological anatomical approach
Aliso, 2007Co-Authors: Manuel Pimentel, Elvira SahuquilloAbstract:The genus Anthoxanthum s.I. (including Hierochloe) (Poaceae, Pooideae, Aveneae) comprises 35-50 species and has a cosmopolitan distribution. Anthoxanthum alpinum was described as a diploid perennial that is distributed in northern Eurasia and in the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid A. odoratum have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to provide information that may help clarify the relationships between these taxa. Macromorphologial, micromorphological, and anatomical data were gathered and analyzed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Statistical analyses were carried out to identify the most useful characters for taxonomy. The relationships among samples were based on different similarity coefficients and summarized using UPGMA clustering methods. The results show that geography has more statistical weight than ploidy level in explaining the relatedness among individuals and populations. A strong correlation between leaf micromorphological/anatomical characters and environmental parameters was detected. The results of the analyses do not support recognition of A. alpinum as a distinct species.
Hanisch, Ana Lúcia - One of the best experts on this subject based on the ideXlab platform.
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Produção de forragem e valor nutritivo de fluva sob intervalos de corte
2015Co-Authors: Hanisch, Ana Lúcia, De Arruda Córdova Ulisses, Fonseca Rech Ângela, Lino Rosa JoséAbstract:The experiment was carried out in a field with the objective to evaluate the influence of cutting intervals on dry mass production and nutritional value of Anthoxantum odoratum. Treatments were arranged in a randomized complete blocks design with four replications. The treatments were constituted by four cutting intervals (28, 35, 42 and 49 days). After cuttings, at a distant 7 cm from soil, 140 kg/ha of N, in the urea form, was applied to all treatments. Twelve cuttings were carried out at 28 day-intervals, ten at 35 day-intervals, eight at 42 day-intervals and seven at a 49 day-interval. The dry matter yield decreased quadratically (P
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PRODUÇÃO DE FORRAGEM E VALOR NUTRITIVO DE FLUVA SOB INTERVALOS DE CORTE
'Universidade Federal do Parana', 2015Co-Authors: Hanisch, Ana Lúcia, CÓrdova, Ulisses De Arruda, Rech, Ângela Fonseca, Rosa, José LinoAbstract:O experimento foi conduzido em campo, em uma pastagem de fluva (Anthoxantum odoratum L.) formada há um ano, com o objetivo de avaliar o efeito de diferentes intervalos de corte na produção de massa seca e valor nutritivo do pasto. Foi utilizado delineamento experimental em blocos casualizados, com quatro repetições e quatro tratamentos de intervalos entre corte (28, 35, 42 e 49 dias). Foram aplicados 140 kg ha-1 ano-1 de nitrogênio, na forma de uréia, em todos os tratamentos e o pasto foi cortado a uma altura de 7 cm do solo. Foram realizados 12, 10, 8 e 7 cortes, respectivamente, para os intervalos de 28, 35, 42 e 49 dias. A produção de massa seca reduziu de forma quadrática (P
Elvira Sahuquillo - One of the best experts on this subject based on the ideXlab platform.
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Relationships between the close congeners Anthoxanthum odoratum and A. alpinum (Poaceae, Pooideae) assessed by morphological and molecular methods
Botanical Journal of the Linnean Society, 2008Co-Authors: Manuel Pimentel, Elvira SahuquilloAbstract:Anthoxanthum alpinum Love & Love has been described as a diploid perennial distributed in northern Eurasia and the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid Anthoxanthum odoratum L. have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to use different approaches to assess the relationships between close congeners, such as the pair A. odoratum/A. alpinum. Macromorphological, micromorphological, and molecular data were gathered and analysed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Different cluster analyses were performed to study the relatedness between individuals and populations. Subsequently, a principal components analysis was computed on the basis of macromorphological quantitative traits, and principal coordinates analysis was used to analyse qualitative, micromorphological, and random amplification of polymorphic DNA (RAPD) data. An analysis of molecular variance was applied to the molecular data, and the genetic differentiation between samples was measured using the FST estimator. The results showed that the geographical origin was more important than the ploidy level in explaining the relatedness between specimens and populations. Moreover, a strong correlation was found between the micromorphological traits and environmental parameters. The results of the analyses do not support the assignment of a specific taxonomic rank to A. alpinum. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 156, 237–252.
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relationships among some populations of Anthoxanthum alpinum and a odoratum poaceae pooideae a morphological anatomical approach
Aliso, 2007Co-Authors: Manuel Pimentel, Elvira SahuquilloAbstract:The genus Anthoxanthum s.I. (including Hierochloe) (Poaceae, Pooideae, Aveneae) comprises 35-50 species and has a cosmopolitan distribution. Anthoxanthum alpinum was described as a diploid perennial that is distributed in northern Eurasia and in the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid A. odoratum have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to provide information that may help clarify the relationships between these taxa. Macromorphologial, micromorphological, and anatomical data were gathered and analyzed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Statistical analyses were carried out to identify the most useful characters for taxonomy. The relationships among samples were based on different similarity coefficients and summarized using UPGMA clustering methods. The results show that geography has more statistical weight than ploidy level in explaining the relatedness among individuals and populations. A strong correlation between leaf micromorphological/anatomical characters and environmental parameters was detected. The results of the analyses do not support recognition of A. alpinum as a distinct species.