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Myriam Carolina Peichoto - One of the best experts on this subject based on the ideXlab platform.

  • a new allopolyploid species of saccharum poaceae Andropogoneae from south america with notes on its cytogenetics
    Systematic Botany, 2017
    Co-Authors: Cassiano A D Welker, Elizabeth A. Kellogg, Tatiana T Souzachies, Myriam Carolina Peichoto, Reyjane P Oliveira, Luana Carvalho, Victoria B S Muccillo, Eliane Kaltchuksantos
    Abstract:

    Allopolyploidy is a major mode of speciation in flowering plants and particularly in the grass tribe Andropogoneae, which includes sugarcane (Saccharum officinarum) and relatives. A new species of Saccharum from South America (S. intermedium) is described here, supported by morphological, molecular and cytogenetic evidence. Previous molecular analyses indicated an allopolyploid origin of the new species through interspecific hybridization between S. angustifolium and S. villosum. The new taxon has intermediate morphology between the two parental species. Cytogenetic analyses of the three species were performed, including chromosome counts, meiotic regularity, and pollen viability and morphology. The new taxon is hexaploid (2n = 60), while the parental species are triploids (2n = 30), confirming the ploidy level suggested by the number of paralogues in phylogenetic trees based on low-copy nuclear genes. This represents the first chromosome count for S. intermedium and a new cytotype for S. villosum. Although both parental species are triploids, they surprisingly exhibited regular meiosis and high pollen viability, indicating they are male-fertile, as is the hexaploid new species. Data on geographic distribution and phenology is also presented, aswell as a key for the South American species of Saccharum.

  • morphometric analysis of schizachyrium poaceae Andropogoneae reveals two new species from south america
    Systematic Botany, 2015
    Co-Authors: Myriam Carolina Peichoto, Cassiano A D Welker, Viviana Solis G Neffa
    Abstract:

    Fil: Peichoto, Myriam Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Botanica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botanica del Nordeste; Argentina

  • considerations on the genus schizachyrium poaceae Andropogoneae in central america and west indies and confirmation of the occurrence of s glaziovii
    Phytotaxa, 2015
    Co-Authors: Cassiano A D Welker, Myriam Carolina Peichoto
    Abstract:

    Schizachyrium (Poaceae–Andropogoneae) includes ca. 60 species, 10 of them previously cited for Central America and 13 for West Indies. The confirmation of the occurrence of Schizachyrium glaziovii in these regions is reported here, expanding its northern limit of distribution to Guatemala and Belize. The species was previously accepted only for South America. We provide a description of the species, a distribution map, and a key to distinguish it from S. microstachyum and S. condensatum , species whose circumscriptions are confused in floras of Central America and West Indies. Taxonomic comments, illustrations of the type materials and images of the three species are also provided. A revised synonymy of S. glaziovii is presented and a lectotype for Andropogon condensatus subsp. elongatus (a synonym of Schizachyrium glaziovii ) is designated here.

  • revision taxonomica de las especies del genero schizachyrium poaceae Andropogoneae de sudamerica
    Candollea, 2010
    Co-Authors: Myriam Carolina Peichoto
    Abstract:

    Fil: Peichoto, Myriam Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Nordeste. Instituto de Botanica del Nordeste (i); Argentina

  • identity of schizachyrium sulcatum and s brevifolium poaceae Andropogoneae
    Brittonia, 2007
    Co-Authors: Myriam Carolina Peichoto, Maria Mercedes Arbo, Zulma Rugolo E De Agrasar, Viviana Solis G Neffa
    Abstract:

    Abstract Schizachyrium sulcatum, distributed in Brazil, Bolivia and Colombia, is described, illustrated, and reported for the first time from Peru and Venezuela. Synonymy, geographical distribution, ecology, and a list of representative specimens examined are provided. Characters of taxonomic value are established in order to differentiate this species from S. brevifolium. A comparative study based on morphology, leaf anatomy, and micromorphological features of the spikelets and leaf blade are included. The multivariate analysis based on morphological variables allows S. sulcatum to be distinguished clearly from S. brevifolium.

Lidia Raquel Scrivanti - One of the best experts on this subject based on the ideXlab platform.

  • phylogeny evolution and ecological speciation analyses of imperata poaceae Andropogoneae in the neotropics
    Systematics and Biodiversity, 2021
    Co-Authors: Fernando Moro Cordobes, Ana M. Anton, Federico Omar Robbiati, Lidia Raquel Scrivanti
    Abstract:

    Imperata is a ubiquitous grass genus of the tribe Andropogoneae (Poaceae), distributed throughout the world. Previous systematic studies had established that the genus encompasses nine species alth...

  • allelopathic effect of endemic south american bothriochloa species poaceae Andropogoneae
    Journal of Essential Oil Research, 2019
    Co-Authors: Lidia Raquel Scrivanti, Ana M. Anton
    Abstract:

    The essential oil composition of Bothriochloa velutina has been studied. The principal compounds of essential oils of three South American endemics, B. eurylemma, B. meridionalis and B. velutina we...

  • allelopathic potential of south american bothriochloa species poaceae Andropogoneae
    2011
    Co-Authors: Lidia Raquel Scrivanti, Ana M. Anton, Julio A Zygadlo
    Abstract:

    In laboratory bioassays the aqueous extracts from different plant parts of six Bothriochloa species (B. barbinodis, B. edwardsiana, B. perforata, B. saccharoides,. var. saccharoides and B. springfieldii) inhibited the seed germination and root and shoot growth of lettuce ( Lactuca sativa L.), maize ( Zea mays L.), wintergreen paspalum ( Paspalum guenoarum Arechav.) and lovegrass [ Eragrostis curvula (Schrad.) Nees)] test species. Aqueous extracts were more inhibitory to shoot and root elongation than to seed germination. Significant inhibition in shoot length at all concentrations indicated the phytotoxic activity of extracts. The toxicity enhanced with increasing aqueous extract concentrations. Perhaps these extracts may contain allelochemicals, which interferes with seed germination and seedling growth of plants. Consequently, the study of these chemical interactions might be useful to develop new classes of environmentally safe herbicides. Key Word: Allelopathy, aqueous extracts, Bothriochloa , inhibition, Poaceae, root growth, seed germination, shoot growth

  • allelopathic potential of bothriochloa laguroides var laguroides dc herter poaceae Andropogoneae
    Flora, 2010
    Co-Authors: Lidia Raquel Scrivanti
    Abstract:

    Bothriochloa laguroides var. laguroides (DC.) Herter, a native bluestem of America, has been shown to produce many biologically active compounds. The allelopathic potential of aqueous extracts from roots, stems and leaves was examined. Lettuce seeds (Lactuca sativa) and maize (Zea mays), the common allelopathy bioassay systems, as well as seeds from two native species, wintergreen paspalum (Paspalum guenoarum) and lovegrass (Eragrostis curvula), were germinated in the presence of aqueous extracts. Percent seed germination, root and shoot elongation were measured. After 4 and 7 days root, stem and leaf extracts caused inhibition of root and shoot elongation in all four species tested. Aqueous extracts were generally less inhibitory to seed germination. Aqueous extracts from different parts of B. laguroides var. laguroides show therefore allelopathic effects inhibiting, in particular, growth of competing plants.

  • reproductive biology of south american bothriochloa poaceae Andropogoneae
    Flora, 2009
    Co-Authors: Lidia Raquel Scrivanti, Guillermo Alberto Norrmann, Ana M. Anton
    Abstract:

    The reproductive biology of 13 South American taxa of Bothriochloa was studied. All surveyed species reproduce sexually and are self-compatible. Several elements also point to self-pollination as their main breeding system: (i) bud pollination that occurs in most species enhancing cleistogamy, (ii) presence of pits in the glumes that impede the opening of flowers and (iii) reduction in the number of stamens, a trend associated with outbreeding.

Cassiano A D Welker - One of the best experts on this subject based on the ideXlab platform.

  • clarifying the type of the polyphyletic genus schizachyrium poaceae Andropogoneae
    Kew Bulletin, 2021
    Co-Authors: Cassiano A D Welker, Elizabeth A. Kellogg, Jefferson Prado, Kanchi N Gandhi
    Abstract:

    Schizachyrium Nees is one of the largest genera of the grass tribe Andropogoneae and is clearly polyphyletic, including at least three distinct lineages. For more than a century, the type of Schizachyrium has been the subject of disagreement in the literature, with most authors considering it to be S. brevifolium (Sw.) Nees ex Buse, but others accepting S. condensatum (Kunth) Nees. Our investigation confirmed that the earliest effective typification of Schizachyrium was performed by Pfeiffer (1874) and thus S. condensatum is the correct type of the genus. Elucidation of this issue is crucial for the future taxonomic rearrangements of this polyphyletic genus since its type will define which lineage will retain the generic name Schizachyrium.

  • lectotypification of the names of all accepted species of agenium poaceae Andropogoneae
    Phytotaxa, 2019
    Co-Authors: Mitchel Iago Alves Costa, Fernando O Zuloaga, Cassiano A D Welker
    Abstract:

    Agenium is a taxonomically complicated and poorly known grass genus, comprising four species from South America. In this paper, lectotypes are designated for the names of all accepted species of Agenium ( A. goyazense , A. leptocladum , A. majus , and A. villosum ), and images of the chosen lectotypes are presented.

  • a new allopolyploid species of saccharum poaceae Andropogoneae from south america with notes on its cytogenetics
    Systematic Botany, 2017
    Co-Authors: Cassiano A D Welker, Elizabeth A. Kellogg, Tatiana T Souzachies, Myriam Carolina Peichoto, Reyjane P Oliveira, Luana Carvalho, Victoria B S Muccillo, Eliane Kaltchuksantos
    Abstract:

    Allopolyploidy is a major mode of speciation in flowering plants and particularly in the grass tribe Andropogoneae, which includes sugarcane (Saccharum officinarum) and relatives. A new species of Saccharum from South America (S. intermedium) is described here, supported by morphological, molecular and cytogenetic evidence. Previous molecular analyses indicated an allopolyploid origin of the new species through interspecific hybridization between S. angustifolium and S. villosum. The new taxon has intermediate morphology between the two parental species. Cytogenetic analyses of the three species were performed, including chromosome counts, meiotic regularity, and pollen viability and morphology. The new taxon is hexaploid (2n = 60), while the parental species are triploids (2n = 30), confirming the ploidy level suggested by the number of paralogues in phylogenetic trees based on low-copy nuclear genes. This represents the first chromosome count for S. intermedium and a new cytotype for S. villosum. Although both parental species are triploids, they surprisingly exhibited regular meiosis and high pollen viability, indicating they are male-fertile, as is the hexaploid new species. Data on geographic distribution and phenology is also presented, aswell as a key for the South American species of Saccharum.

  • morphometric analysis of schizachyrium poaceae Andropogoneae reveals two new species from south america
    Systematic Botany, 2015
    Co-Authors: Myriam Carolina Peichoto, Cassiano A D Welker, Viviana Solis G Neffa
    Abstract:

    Fil: Peichoto, Myriam Carolina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Botanica del Nordeste. Universidad Nacional del Nordeste. Facultad de Ciencias Agrarias. Instituto de Botanica del Nordeste; Argentina

  • considerations on the genus schizachyrium poaceae Andropogoneae in central america and west indies and confirmation of the occurrence of s glaziovii
    Phytotaxa, 2015
    Co-Authors: Cassiano A D Welker, Myriam Carolina Peichoto
    Abstract:

    Schizachyrium (Poaceae–Andropogoneae) includes ca. 60 species, 10 of them previously cited for Central America and 13 for West Indies. The confirmation of the occurrence of Schizachyrium glaziovii in these regions is reported here, expanding its northern limit of distribution to Guatemala and Belize. The species was previously accepted only for South America. We provide a description of the species, a distribution map, and a key to distinguish it from S. microstachyum and S. condensatum , species whose circumscriptions are confused in floras of Central America and West Indies. Taxonomic comments, illustrations of the type materials and images of the three species are also provided. A revised synonymy of S. glaziovii is presented and a lectotype for Andropogon condensatus subsp. elongatus (a synonym of Schizachyrium glaziovii ) is designated here.

Ana M. Anton - One of the best experts on this subject based on the ideXlab platform.

Elizabeth A. Kellogg - One of the best experts on this subject based on the ideXlab platform.

  • clarifying the type of the polyphyletic genus schizachyrium poaceae Andropogoneae
    Kew Bulletin, 2021
    Co-Authors: Cassiano A D Welker, Elizabeth A. Kellogg, Jefferson Prado, Kanchi N Gandhi
    Abstract:

    Schizachyrium Nees is one of the largest genera of the grass tribe Andropogoneae and is clearly polyphyletic, including at least three distinct lineages. For more than a century, the type of Schizachyrium has been the subject of disagreement in the literature, with most authors considering it to be S. brevifolium (Sw.) Nees ex Buse, but others accepting S. condensatum (Kunth) Nees. Our investigation confirmed that the earliest effective typification of Schizachyrium was performed by Pfeiffer (1874) and thus S. condensatum is the correct type of the genus. Elucidation of this issue is crucial for the future taxonomic rearrangements of this polyphyletic genus since its type will define which lineage will retain the generic name Schizachyrium.

  • continued adaptation of c4 photosynthesis after an initial burst of changes in the Andropogoneae grasses
    Systematic Biology, 2020
    Co-Authors: Matheus E Bianconi, Watchara Arthan, Jan Hackel, Maria S Vorontsova, Adriana Alberti, Sean V Burke, Melvin R Duvall, Elizabeth A. Kellogg
    Abstract:

    C$_{4}$ photosynthesis is a complex trait that sustains fast growth and high productivity in tropical and subtropical conditions and evolved repeatedly in flowering plants. One of the major C$_{4}$ lineages is Andropogoneae, a group of $\sim $1200 grass species that includes some of the world's most important crops and species dominating tropical and some temperate grasslands. Previous efforts to understand C$_{4}$ evolution in the group have compared a few model C$_{4}$ plants to distantly related C$_{3}$ species so that changes directly responsible for the transition to C$_{4}$ could not be distinguished from those that preceded or followed it. In this study, we analyze the genomes of 66 grass species, capturing the earliest diversification within Andropogoneae as well as their C$_{3}$ relatives. Phylogenomics combined with molecular dating and analyses of protein evolution show that many changes linked to the evolution of C$_{4}$ photosynthesis in Andropogoneae happened in the Early Miocene, between 21 and 18 Ma, after the split from its C$_{3}$ sister lineage, and before the diversification of the group. This initial burst of changes was followed by an extended period of modifications to leaf anatomy and biochemistry during the diversification of Andropogoneae, so that a single C$_{4}$ origin gave birth to a diversity of C$_{4}$ phenotypes during 18 million years of speciation events and migration across geographic and ecological spaces. Our comprehensive approach and broad sampling of the diversity in the group reveals that one key transition can lead to a plethora of phenotypes following sustained adaptation of the ancestral state. [Adaptive evolution; complex traits; herbarium genomics; Jansenelleae; leaf anatomy; Poaceae; phylogenomics.].

  • Phylogenomics of Andropogoneae (Panicoideae: Poaceae) of Mainland Southeast Asia
    Systematic Botany, 2017
    Co-Authors: Watchara Arthan, Cassiano Aimberê Dorneles Welker, Michael R Mckain, Paweena Traiperm, Jordan K. Teisher, Elizabeth A. Kellogg
    Abstract:

    The grass tribe Andropogoneae is distributed in warm regions around the globe but has been poorly studied in mainland Southeast Asia. This is particularly true for the cosmopolitan genera Andropogon and Schizachyrium, with several species that appear to be narrowly distributed in this region. Additionally, lesser-known species in the genera Hemisorghum, Kerriochloa, and Pseudosorghum also occur inmainland Southeast Asia. A phylogeny is needed to address questions of taxonomy and trait evolution. Whole chloroplast genomes of Andropogoneae species and two outgroup species of Garnotia (tribe Arundinelleae) were analyzed using maximum likelihood (ML) and Bayesian inference (BI). Ancestral character states were reconstructed usingML for four morphological characters key to Andropogon and Schizachyrium identification.Apreviously-unidentified clade of Southeast Asian endemic taxa is found, including one species formerly classified in Andropogon. Other Southeast Asian taxa fall in an unresolved grade outside the major radiation of the tribe. Andropogon and Schizachyrium are both polyphyletic. Convergent evolution and reversal of characters are common throughout Andropogoneae. Addition of species from mainland Southeast Asian finds unexpected phylogenetic diversity. Southeast Asian Schizachyrium sanguineum forms two separate clades, which could reflect cryptic species differentiation, hybridization, introgression, or some combination.

  • a new allopolyploid species of saccharum poaceae Andropogoneae from south america with notes on its cytogenetics
    Systematic Botany, 2017
    Co-Authors: Cassiano A D Welker, Elizabeth A. Kellogg, Tatiana T Souzachies, Myriam Carolina Peichoto, Reyjane P Oliveira, Luana Carvalho, Victoria B S Muccillo, Eliane Kaltchuksantos
    Abstract:

    Allopolyploidy is a major mode of speciation in flowering plants and particularly in the grass tribe Andropogoneae, which includes sugarcane (Saccharum officinarum) and relatives. A new species of Saccharum from South America (S. intermedium) is described here, supported by morphological, molecular and cytogenetic evidence. Previous molecular analyses indicated an allopolyploid origin of the new species through interspecific hybridization between S. angustifolium and S. villosum. The new taxon has intermediate morphology between the two parental species. Cytogenetic analyses of the three species were performed, including chromosome counts, meiotic regularity, and pollen viability and morphology. The new taxon is hexaploid (2n = 60), while the parental species are triploids (2n = 30), confirming the ploidy level suggested by the number of paralogues in phylogenetic trees based on low-copy nuclear genes. This represents the first chromosome count for S. intermedium and a new cytotype for S. villosum. Although both parental species are triploids, they surprisingly exhibited regular meiosis and high pollen viability, indicating they are male-fertile, as is the hexaploid new species. Data on geographic distribution and phenology is also presented, aswell as a key for the South American species of Saccharum.

  • patterns of inflorescence development of three prairie grasses Andropogoneae poaceae
    International Journal of Plant Sciences, 2014
    Co-Authors: John G Hodge, Elizabeth A. Kellogg
    Abstract:

    Premise of research. The tribe Andropogoneae (Poaceae) is a morphologically diverse clade that is distributed worldwide; members of the tribe are ecological dominants in some of the world’s most expansive grasslands. Inflorescence morphology in the tribe is variable and does not indicate relationship, creating problems for systematic treatments of morphological characters. Closely related taxa may have different pollination syndromes and ecological roles, correlating with substantially different morphology.Methodology. To determine when morphological differences arise in developmental time, we investigated three species endemic to North American tallgrass prairies: big bluestem (Andropogon gerardi), little bluestem (Schizachyrium scoparium), and the inbreeding broomsedge bluestem (Andropogon virginicus). These species are widespread, common, and often ecologically dominant, but their development has never been studied. We used SEM to sample inflorescences from initiation to anthesis.Pivotal results. Both ...