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John H Wiersema - One of the best experts on this subject based on the ideXlab platform.
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Towards a complete species tree of Nymphaea: shedding further light on subg. Brachyceras and its relationships to the Australian water-lilies
2011Co-Authors: Thomas Borsch, Cornelia Lohne, Mame Samba Mbaye, John H WiersemaAbstract:The water-lily genus Nymphaea exhibits a worldwide distribution with an estimated number of more than 50 extant species. Recent phylogenetic analyses resolved three major lineages, a subg. Brachyceras–subg. Anecphya clade, also including Nymphaea ondinea, a subg. Hydrocallis-subg. Lotos clade, and the temperate subg. Nymphaea as a third clade. This study extends the taxon sampling for Brachyceras, previously the least understood subgenus. Maximum Parsimony and Bayesian analysis of nrITS sequence data depict a monophyletic subg. Brachyceras-clade and show a New World clade to be nested within African taxa. Plastid trnT-trnF sequence data are less conclusive. A middle Miocene origin is inferred for the New World Brachyceras lineage that must have dispersed out of Africa either via a Beringian migrational route or through immediate long distance dispersal. Within subg. Brachyceras, the West African individuals of Nymphaea guineensis form a distinct clade in both nuclear and plastid trees to which the Madagascan Nymphaea minuta is sister. Central and East African Brachyceras species appear well separated, suggesting a separating effect of the Dahomey gap to the evolution of these species. ITS sequences are more powerful in identifying Nymphaea species than trnT–trnF sequences. Nevertheless, about 15% of the known species remain to be sampled for a complete molecular tree of water-lilies. This also requires sampling of multiple populations in order to discover entities with a common evolutionary history and distinct molecular and morphological characters.
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The unusual Ondinea, actually just another Australian water-lily of Nymphaea subg. Anecphya (Nymphaeaceae)
Willdenowia, 2009Co-Authors: Cornelia Lohne, John H Wiersema, Thomas BorschAbstract:Abstract Lohne C., Wiersema J. H. & Borsch T.: The unusual Ondinea, actually just another Australian water-lily of Nymphaea subg. Anecphya (Nymphaeaceae). — Willdenowia 39: 55–58. — Online ISSN 1868-6397; © 2009 BGBM Berlin-Dahlem. doi:10.3372/wi.39.39104 (available via http://dx.doi.org/) Based on recent findings of phylogenetic studies using character sets from all three genomic compartments and from morphology, Ondinea purpurea is transferred to Nymphaea and the new name N. ondinea is validly published. This change in classification implements the criterion that higher taxa should be monophyletic. Although, compared to other species of Nymphaea, the Australian N. ondinea appears to be phenotypically very different, most shifts in character states that led to its evolution (e.g., loss of perianth in some of the populations, decrease in stamen and carpel number) are rather quantitative. Several characters not only support a position of Ondinea within Nymphaea (such as an eusyncarpous gynoeceum with carpe...
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Phylogeny of Nymphaea (Nymphaeaceae): Evidence from Substitutions and Microstructural Changes in the Chloroplast trnT‐trnF Region
International Journal of Plant Sciences, 2007Co-Authors: Thomas Borsch, Wilhelm Barthlott, John H Wiersema, Cornelia Lohne, Khidir W. Hilu, Volker WildeAbstract:Nymphaea is the most speciose, phenotypically diverse, and geographically widespread (nearly global) genus of Nymphaeales. Phylogenetic relationships among 35 of an estimated 45–50 species of Nymphaea are presented based on an analysis of the chloroplast trnT‐trnF region. Because this is the first phylogenetic analysis of Nymphaea, monophyly of the genus had to be tested, and its status in Nymphaeales had to be inferred. Rooting was therefore extended to more distant outgroups (Amborella, Austrobaileyales). Monophyly of Nymphaea received weak support, with a Euryale‐Victoria clade appearing as sister. The three major lineages within Nymphaea are constituted by the northern temperate subg. Nymphaea that is sister to all remaining species, a subgg. Hydrocallis‐Lotos clade, and a subgg. Anecphya‐Brachyceras clade. The Australian genus Ondinea was nested at species level within Nymphaea subg. Anecphya. The pantropical subg. Brachyceras as currently circumscribed does not appear natural, with Nymphaea petersia...
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phylogeny of Nymphaea Nymphaeaceae evidence from substitutions and microstructural changes in the chloroplast trnt trnf region
International Journal of Plant Sciences, 2007Co-Authors: Thomas Borsch, Wilhelm Barthlott, John H Wiersema, Cornelia Lohne, Khidir W. Hilu, Volker WildeAbstract:Nymphaea is the most speciose, phenotypically diverse, and geographically widespread (nearly global) genus of Nymphaeales. Phylogenetic relationships among 35 of an estimated 45–50 species of Nymphaea are presented based on an analysis of the chloroplast trnT‐trnF region. Because this is the first phylogenetic analysis of Nymphaea, monophyly of the genus had to be tested, and its status in Nymphaeales had to be inferred. Rooting was therefore extended to more distant outgroups (Amborella, Austrobaileyales). Monophyly of Nymphaea received weak support, with a Euryale‐Victoria clade appearing as sister. The three major lineages within Nymphaea are constituted by the northern temperate subg. Nymphaea that is sister to all remaining species, a subgg. Hydrocallis‐Lotos clade, and a subgg. Anecphya‐Brachyceras clade. The Australian genus Ondinea was nested at species level within Nymphaea subg. Anecphya. The pantropical subg. Brachyceras as currently circumscribed does not appear natural, with Nymphaea petersia...
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Nymphaea tetragona and Nymphaea leibergii (Nymphaeaceae): two species of diminutive water-lilies in North America
Brittonia, 1996Co-Authors: John H WiersemaAbstract:Although all past floras of northern North America have recognized only one species of diminutive water-lily, actually two distinct species occur in the region. The circumboreal Nymphaea tetragona Georgi is largely confined to the northwestern part of the continent, extending as far east as Manitoba and occurring in the contiguous United States only in northwest Washington. A second species, N. leibergii Morong, is restricted to, but widely distributed in, northern North America, though it is absent from the extreme northwest. The two species are distinguishable from each other by several floral and foliar characters and the two species form a section, Nymphaea subg. Nymphaea sects. ChamaeNymphaea , stat: nov. This is distinguished from the two other sections of subg. Nymphaea in a key, and Nymphaea subg. Nymphaea sect. Xanthantha , stat. nov., is proposed. Sect. ChamaeNymphaea is described for North America, synonymy and nomenclature for both species are discussed, and a key including N. odorata Aiton is presented. A lectotype is provided for N. leibergii and the typification of N. tetragona is examined.
Thomas Borsch - One of the best experts on this subject based on the ideXlab platform.
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Towards a complete species tree of Nymphaea: shedding further light on subg. Brachyceras and its relationships to the Australian water-lilies
2011Co-Authors: Thomas Borsch, Cornelia Lohne, Mame Samba Mbaye, John H WiersemaAbstract:The water-lily genus Nymphaea exhibits a worldwide distribution with an estimated number of more than 50 extant species. Recent phylogenetic analyses resolved three major lineages, a subg. Brachyceras–subg. Anecphya clade, also including Nymphaea ondinea, a subg. Hydrocallis-subg. Lotos clade, and the temperate subg. Nymphaea as a third clade. This study extends the taxon sampling for Brachyceras, previously the least understood subgenus. Maximum Parsimony and Bayesian analysis of nrITS sequence data depict a monophyletic subg. Brachyceras-clade and show a New World clade to be nested within African taxa. Plastid trnT-trnF sequence data are less conclusive. A middle Miocene origin is inferred for the New World Brachyceras lineage that must have dispersed out of Africa either via a Beringian migrational route or through immediate long distance dispersal. Within subg. Brachyceras, the West African individuals of Nymphaea guineensis form a distinct clade in both nuclear and plastid trees to which the Madagascan Nymphaea minuta is sister. Central and East African Brachyceras species appear well separated, suggesting a separating effect of the Dahomey gap to the evolution of these species. ITS sequences are more powerful in identifying Nymphaea species than trnT–trnF sequences. Nevertheless, about 15% of the known species remain to be sampled for a complete molecular tree of water-lilies. This also requires sampling of multiple populations in order to discover entities with a common evolutionary history and distinct molecular and morphological characters.
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The unusual Ondinea, actually just another Australian water-lily of Nymphaea subg. Anecphya (Nymphaeaceae)
Willdenowia, 2009Co-Authors: Cornelia Lohne, John H Wiersema, Thomas BorschAbstract:Abstract Lohne C., Wiersema J. H. & Borsch T.: The unusual Ondinea, actually just another Australian water-lily of Nymphaea subg. Anecphya (Nymphaeaceae). — Willdenowia 39: 55–58. — Online ISSN 1868-6397; © 2009 BGBM Berlin-Dahlem. doi:10.3372/wi.39.39104 (available via http://dx.doi.org/) Based on recent findings of phylogenetic studies using character sets from all three genomic compartments and from morphology, Ondinea purpurea is transferred to Nymphaea and the new name N. ondinea is validly published. This change in classification implements the criterion that higher taxa should be monophyletic. Although, compared to other species of Nymphaea, the Australian N. ondinea appears to be phenotypically very different, most shifts in character states that led to its evolution (e.g., loss of perianth in some of the populations, decrease in stamen and carpel number) are rather quantitative. Several characters not only support a position of Ondinea within Nymphaea (such as an eusyncarpous gynoeceum with carpe...
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Phylogeny of Nymphaea (Nymphaeaceae): Evidence from Substitutions and Microstructural Changes in the Chloroplast trnT‐trnF Region
International Journal of Plant Sciences, 2007Co-Authors: Thomas Borsch, Wilhelm Barthlott, John H Wiersema, Cornelia Lohne, Khidir W. Hilu, Volker WildeAbstract:Nymphaea is the most speciose, phenotypically diverse, and geographically widespread (nearly global) genus of Nymphaeales. Phylogenetic relationships among 35 of an estimated 45–50 species of Nymphaea are presented based on an analysis of the chloroplast trnT‐trnF region. Because this is the first phylogenetic analysis of Nymphaea, monophyly of the genus had to be tested, and its status in Nymphaeales had to be inferred. Rooting was therefore extended to more distant outgroups (Amborella, Austrobaileyales). Monophyly of Nymphaea received weak support, with a Euryale‐Victoria clade appearing as sister. The three major lineages within Nymphaea are constituted by the northern temperate subg. Nymphaea that is sister to all remaining species, a subgg. Hydrocallis‐Lotos clade, and a subgg. Anecphya‐Brachyceras clade. The Australian genus Ondinea was nested at species level within Nymphaea subg. Anecphya. The pantropical subg. Brachyceras as currently circumscribed does not appear natural, with Nymphaea petersia...
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phylogeny of Nymphaea Nymphaeaceae evidence from substitutions and microstructural changes in the chloroplast trnt trnf region
International Journal of Plant Sciences, 2007Co-Authors: Thomas Borsch, Wilhelm Barthlott, John H Wiersema, Cornelia Lohne, Khidir W. Hilu, Volker WildeAbstract:Nymphaea is the most speciose, phenotypically diverse, and geographically widespread (nearly global) genus of Nymphaeales. Phylogenetic relationships among 35 of an estimated 45–50 species of Nymphaea are presented based on an analysis of the chloroplast trnT‐trnF region. Because this is the first phylogenetic analysis of Nymphaea, monophyly of the genus had to be tested, and its status in Nymphaeales had to be inferred. Rooting was therefore extended to more distant outgroups (Amborella, Austrobaileyales). Monophyly of Nymphaea received weak support, with a Euryale‐Victoria clade appearing as sister. The three major lineages within Nymphaea are constituted by the northern temperate subg. Nymphaea that is sister to all remaining species, a subgg. Hydrocallis‐Lotos clade, and a subgg. Anecphya‐Brachyceras clade. The Australian genus Ondinea was nested at species level within Nymphaea subg. Anecphya. The pantropical subg. Brachyceras as currently circumscribed does not appear natural, with Nymphaea petersia...
María Silvia Ferrucci - One of the best experts on this subject based on the ideXlab platform.
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Carpellary appendages in Nymphaea and Victoria (Nymphaeaceae): evidence of their role as osmophores based on morphology, anatomy and ultrastructure
Botanical Journal of the Linnean Society, 2019Co-Authors: Lucía Melisa Zini, Beatriz G. Galati, Marina M. Gotelli, Gabriela Zarlavsky, María Silvia FerrucciAbstract:Abstract In flowers of Nymphaea and Victoria, carpellary appendages are regarded as structures related to pollination by deceit of night-blooming species. In this study, the anatomy, histochemistry and ultrastructure of carpellary appendages were analysed to investigate their possible role in the production of volatile compounds in nocturnal species Nymphaea amazonum, N. gardneriana, N. prolifera (Nymphaea subgenus Hydrocallis) and Victoria cruziana, and in diurnal species N. caerulea (Nymphaea subgenus Brachyceras). Carpellary appendages were studied using light microscopy and scanning and transmission electron microscopy from pre-anthesis to the second day of anthesis. Anatomical and ultrastructural features are characteristic of osmophores. In all species, the most frequent components in secretory cells are amyloplasts, lipid bodies, mitochondria, rough endoplasmic reticulum and elaioplasts. The epidermis and multilayered parenchyma accumulate abundant starch grains and lipophilic substances, both of which vanish during anthesis. Amorphous substances are deposited between the plasmalemma and the outer cell wall of epidermal cells, and are then released by cuticular diffusion. Odour production in carpellary appendages might be an ancient role of primary importance both in diurnal and nocturnal species that are pollinated by deceit. Olfactory and visual cues of small carpellary appendages in Nymphaea subgenus Brachyceras correspond to bee pollination, and large carpellary appendages in subgenus Hydrocallis and Victoria represent parallel functional specializations of the flowers to the attraction and reward for exclusive beetle pollination.
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Ovule and female gametophyte in representatives of Nymphaea subgenus Hydrocallis and Victoria (Nymphaeaceae; Nymphaeoideae)
Aquatic Botany, 2015Co-Authors: Lucía Melisa Zini, Beatriz G. Galati, María Silvia FerrucciAbstract:Abstract Nymphaeaceae occupies an important phylogenetic position because of their placement as one of the basal angiosperms. From this perspective, morphological studies in the family are of great value to understanding plant phylogeny and evolution. Ovule development and female gametophyte in Nymphaea amazonum, N. gardneriana (subgenus Hydrocallis) and in Victoria cruziana were analyzed in order to provide further progress in characters of potential evolutionary interest. The ovules of all species are anatropous, bitegmic, distomic, weakly crasinucellate, and present an epistase. The female gametophyte is four-celled and corresponds to the Schisandra type, distinctive of the Nymphaeales. Comparisons among ovules of the subgenera of Nymphaea and others allied genera show differences with respect to micropyle conformation, thickness of nucellus and outer integument, and its degree of development on the raphal side. The studied species of Nymphaea share an annular outer integument and linear triad of megaspores. These results fill gaps in the current incomplete knowledge of character states especially within Nymphaea. In subgenus Hydrocallis, the ovules have an outer integument not markedly cup-shaped in contrast to subgenus Nymphaea, since the micropyle is closer to the funiculus as in Nuphar. The present observations suggest that the ovule morphology has diversified in Nymphaea and the characters studied clearly show no evidences to support the hypothesis of a monophyletic genus.
Jack D Rogers - One of the best experts on this subject based on the ideXlab platform.
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morphological and molecular characterization of colletotrichum Nymphaeae and c nupharicola sp nov on water lilies Nymphaea and nuphar
Fungal Biology, 1997Co-Authors: Dennis A. Johnson, Lori M Carris, Jack D RogersAbstract:Nine isolates of a Colletotrichum sp. collected in North America on yellow water-lily (Nuphar luteum subsp. polysepalum) at five locations in the Pacific Northwest (PNW) and one isolate from Nymphaea odorata in Rhode Island were compared to three isolates of C. Nymphaeae occurring on Nymphaea alba and Nuphar luteum in Europe. The appressoria of all North American isolates were significantly wider than those of C. Nymphaeae. Conidia of the nine PNW isolates were significantly wider than those of both the Rhode Island isolate and C. Nymphaeae isolates. All isolates were compared using random amplified polymorphic DNA (RAPD) and restriction fragment length polymorphism of the ITS region (RFLP-ITS). Two distinct clusters were differentiated in the dendrogram based on the RAPD analysis. The ten North American isolates formed one cluster and the European isolates of C. Nymphaeae formed a second cluster. The separation of the North American isolates from the European isolates was supported by distinct restriction digest phenotypes of the ITS region. Based on morphological and molecular characterization the North American fungus is proposed as a new species, C. nupharicola.
Aqueel Khan - One of the best experts on this subject based on the ideXlab platform.
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antihepatotoxic effect of Nymphaea stellata willd against carbon tetrachloride induced hepatic damage in albino rats
Journal of Ethnopharmacology, 2004Co-Authors: Manoj R Bhandarkar, Aqueel KhanAbstract:Nymphaea stellata willd., a medicinal plant mentioned in Ayurveda for the treatment of liver disorders, has not been subjected to systematic scientific investigations to asses its hepatoprotective effects. Therefore, the present study was undertaken to investigate the hepatoprotective activity of extract of Nymphaea stellata willd., flower against carbon tetrachloride-induced hepatic damage in albino rats. The oral administration of varying dosage of extract of Nymphaea stellata willd., flower to rats for 10 days afforded the good hepatoprotection against carbon tetrachloride-induced elevation in serum marker enzymes, serum bilirubin, liver lipid peroxidation and reduction in liver glutathione, liver glutathione peroxidase, glycogen, superoxide dismutase and catalase activity.