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Articles 91 - 117 of 117
Full-Text Articles in Botany
Patterns In Evolution In Characters That Define Iris Subgenera And Sections, Carol A. Wilson
Patterns In Evolution In Characters That Define Iris Subgenera And Sections, Carol A. Wilson
Aliso: A Journal of Systematic and Floristic Botany
Subgeneric groups have been circumscribed in Iris based on a small number of morphological characters. Recent DNA sequence data has indicated that several of the subgenera, sections, and series that have previously been delineated are paraphyletic or polyphyletic. The evolution of characters that have traditionally been used to distinguish sub generic and sectional groups within Iris was investigated by mapping these characters on a phylogenetic tree based on matK sequence data. Results indicate that rhizomes are pleisomorphic for the genus and that three bulb types have arisen independently. My analysis shows that sepal beards, sepal crests, and seed arils …
The Role Of Phylogenetic Constraints In The Evolution Of Pollination Mechanisms In Iridaceae Of Sub-Saharan Africa, Peter Bernhardt, Peter Goldblatt
The Role Of Phylogenetic Constraints In The Evolution Of Pollination Mechanisms In Iridaceae Of Sub-Saharan Africa, Peter Bernhardt, Peter Goldblatt
Aliso: A Journal of Systematic and Floristic Botany
Novel, specialized systems exploiting bibionid flies, oil-collecting bees, wasps, or crepuscular settling moths as pollen vectors are added to the range of recorded pollination mechanisms in sub-Saharan Africa Iridaceae, while knowledge of the pollination of previously understudied genera such as Aristea, Bahiana, Ferraria, Hesperantha, and Tritoniopsis is expanded. The pollination of 357 species of the sub-Saharan African Iridaceae now includes 17 discrete systems. Based on repetitive interlinked suites of floral attractants and rewards we now infer pollination mechanisms for an additional 883 species. Many pollination systems recur in genera containing > 10 species. The ancestral pollination in African Iridaceae, and …
A Comparison And Combination Of Plastid Atpb And Rbcl Gene Sequences For Inferring Phylogenetic Relationships Within Orchidaceae, Kenneth M. Cameron
A Comparison And Combination Of Plastid Atpb And Rbcl Gene Sequences For Inferring Phylogenetic Relationships Within Orchidaceae, Kenneth M. Cameron
Aliso: A Journal of Systematic and Floristic Botany
Parsimony analyses of DNA sequences from the plastid genes atpB and rbcL were completed for 173 species of Orchidaceae (representing 150 different genera) and nine genera from outgroup families in Asparagales. The atpB tree topology is similar to the rbcL tree, although the atpB data contain less homoplasy and provide greater jackknife support than rbcL alone. In combination, the two-gene tree recovers five monophyletic clades corresponding to subfamilies within Orchidaceae, and fully resolves them with moderate to high jackknife support as follows: Epidendroideae are sister to Orchidoideae, followed by Cypripedioideae, then Vanilloideae, and with …
Systematic Floral Anatomy Of Pontederiaceae, Michael G. Simpson, Darren H. Burton
Systematic Floral Anatomy Of Pontederiaceae, Michael G. Simpson, Darren H. Burton
Aliso: A Journal of Systematic and Floristic Botany
Twenty species of Pontederiaceae and six species of the outgroup families Haemodoraceae and Philydraceae were investigated with regard to floral anatomy, using standard histological methods and graphic reconstructions. Variation is described in several features, including functional carpel number, the distribution of floral aerenchyma, the presence of unusual floral epithelial cells, the presence, type, and distribution of tannin cells, crystal type and distribution, aspects of placentation, ovule number, number of ovule rows per carpel, and septal nectary presence. In order to better assess character homology, one of these features, placentation, was divided into three discrete characters: septal fusion, placenta position, and …
Phlogeny And Biogeography Of The Prayer Plant Family, Linda M. Prince, W. John Kress
Phlogeny And Biogeography Of The Prayer Plant Family, Linda M. Prince, W. John Kress
Aliso: A Journal of Systematic and Floristic Botany
Marantaceae are the second largest family in the order Zingiberales, with approximately 31 genera and 535 species. Earlier studies based on morphological and molecular characters could not confidently determine the relationships among major lineages of the family, nor could they identify the basal branch of the family tree. Phylogenetic analyses of DNA sequence data from all three genomic compartments (chloroplast: matK, ndhF, rbcL, rps16 intron, and trnL-trnF intergenic spacer; mitochondrion: cox1; nucleus: ITS region and the 5'-end of 26S) for a restricted set of taxa were conducted under parsimony criteria to define …
Fleshy Fruits In Liliflorous Monocots, Finn N. Rasmussen, Signe Frederikson, Bo Johansen, Lise Bolt Jørgenson, Gitte Peterson
Fleshy Fruits In Liliflorous Monocots, Finn N. Rasmussen, Signe Frederikson, Bo Johansen, Lise Bolt Jørgenson, Gitte Peterson
Aliso: A Journal of Systematic and Floristic Botany
Fleshy fruits occur in several monocot orders and families, and it is generally assumed that they have been derived from capsular fruits many times during the evolution of monocot lineages. Huber hypothesized in 1969 that most capsules in Asparagales are derived secondarily from berries and that this transformation was correlated with the evolution of phytomelan-coated seeds, a pivotal character in his circumscription of Asparagales as part of reclassifying Liliaceae s.l. Dahlgren and co-workers suggested several parallel derivations and "reversals" in this character, e.g., the transformation sequence trifollicular fruits → capsules → berries→ capsules→ berries. Mapping of fleshy fruits on a …
The Never-Ending Story: Multigene Approaches To The Phylogeny Of Amaryllidaceae, Alan W. Meerow, Dierdré A. Snijman
The Never-Ending Story: Multigene Approaches To The Phylogeny Of Amaryllidaceae, Alan W. Meerow, Dierdré A. Snijman
Aliso: A Journal of Systematic and Floristic Botany
a whole, strongly supported the mostly African tribe Amaryllideae as sister to the rest of the family, and resolved geographically-based monophyletic groups, but failed to resolve the relationships among several basal lineages in the family (the African Haemantheae and Cyrtantheae, the Australasian Calostemmateae, and the American and Eurasian sister clades). We present analysis of plastid ndhF sequences that fully resolved the major clades of the family. The baccate-fruited Haemantheae and Calostemmateae are sister tribes, and the African endemic Cyrtantheae is sister to them both. This clade is sister to an American/Eurasian clade. We also present preliminary nuclear ribosomal ITS …
Speciation In Duckweeds (Lemnaceae): Phylogenetic And Ecological Inferences, Daniel J. Crawford, Elias Landolt, Donald H. Les, Rebecca T. Kimball
Speciation In Duckweeds (Lemnaceae): Phylogenetic And Ecological Inferences, Daniel J. Crawford, Elias Landolt, Donald H. Les, Rebecca T. Kimball
Aliso: A Journal of Systematic and Floristic Botany
Species of duckweeds (Letnnaceae) that were resolved as sister taxa in a phylogeny based on combined molecular and non-molecular data were compared for morphological, physiological, and ecological attributes to infer factors important in the initial divergence leading to speciation. The ability to survive extreme conditions such as desiccation and cold temperatures is the most common difference identified between species. Two morphological characters facilitating survival in extreme environments are production of special resting buds called turions and increased seed production. The prevalent geographic pattern for species pairs consists of one restricted species occurring on the periphery of a more widespread taxon; …
Mitochondrial Data In Monocot Phylologenetics, Gitte Peterson, Ole Seberg, Jerrold I. Davis, Douglas H. Goldman, Dennis W. Stevenson, Lisa M. Campbell, Fabian A. Michaelangeli, Chelsea D. Specht, Mark W. Chase, Michael E. Fay, J. Chris Pires, John V. Freudenstein, Christopher R. Hardy, Mark P. Simmons
Mitochondrial Data In Monocot Phylologenetics, Gitte Peterson, Ole Seberg, Jerrold I. Davis, Douglas H. Goldman, Dennis W. Stevenson, Lisa M. Campbell, Fabian A. Michaelangeli, Chelsea D. Specht, Mark W. Chase, Michael E. Fay, J. Chris Pires, John V. Freudenstein, Christopher R. Hardy, Mark P. Simmons
Aliso: A Journal of Systematic and Floristic Botany
Mitochondrial sequences are an important source of data in animal phylogenetics, equivalent in importance to plastid sequences in plants. However, in recent years plant systematists have begun exploring the mitochondrial genome as a source of phylogenetically useful characters. The plant mitochondrial genome is renowned for its variability in size, structure, and gene organization, but this need not be of concern for the application of sequence data in phylogenetics. However, the incorporation of reverse transcribed mitochondrial genes ("processed paralogs") and the recurring transfer of genes from the mitochondrion to the nucleus are evolutionary events that must be taken into account. RNA …
A Phylogenetic Study Of Arecaceae Based On Seedling Morphological And Anatomical Data, Flor M. Henderson, Dennis W. Stevenson
A Phylogenetic Study Of Arecaceae Based On Seedling Morphological And Anatomical Data, Flor M. Henderson, Dennis W. Stevenson
Aliso: A Journal of Systematic and Floristic Botany
A morphological and anatomical survey was carried out of seedlings of 62 taxa of palms representing all major groups. The data were analyzed using cladistic parsimony analysis. Seedling data were analyzed independently and combined with adult morphological data. Outgroup selection was made within the family using the calamoids and Nypa fruticans; outside the family, the monocot family Dasypogonaceae were used. The analysis with the calamoids and Nypa fruticans as outgroups resolved some of the major groups. The combined analysis, using both seedling and adult data and Dasypogonaceae as the outgroup, provided better resolution. Most of the major groups were …
Phylogeny Of Iridaceae Subfamily Crocoideae Based On A Combined Multigene Plastid Dna Analysis, Peter Goldblatt, T. Jonathan Davies, John C. Manning, Michelle Van Der Bank, Vincent Savolainen
Phylogeny Of Iridaceae Subfamily Crocoideae Based On A Combined Multigene Plastid Dna Analysis, Peter Goldblatt, T. Jonathan Davies, John C. Manning, Michelle Van Der Bank, Vincent Savolainen
Aliso: A Journal of Systematic and Floristic Botany
The phylogeny of Crocoideae, the largest of four subfamilies currently recognized in Tridaceae, has eluded resolution until sequences of two more plastid DNA regions were added here to a previously published matrix containing sequences from four DNA plastid regions. Sister to the core Nivenioideae, the woody Klattia, Nivenia, and Witsenia, Crocoideae are a climax group in lridaceae, comprising some 995 species, slightly more than half of the total in the family. Synapomorphies of Crocoideae include pollen exine perforate, pollen aperture operculate, ovule campylotropous (or hypotropous), root xylem vessels with simple perforations, cormous rootstock, inflorescence a spike, and plants deciduous. The …
Phylogenetic Analyses And Biogeography Of Trilliaceae, Susan B. Farmer
Phylogenetic Analyses And Biogeography Of Trilliaceae, Susan B. Farmer
Aliso: A Journal of Systematic and Floristic Botany
Trilliaceae are plants of North Temperate forests with a holarctic distribution and a high degree of endemism. Molecular phylogenetic analyses are presented in order to examine the tribal, generic, and species-level classification of the family. These molecular studies, and earlier morphological studies, support the placement of the genus Pseudotrillium as basal in the family and sister to the tribes Trillieae and Parideae, which are monophyletic sister groups. Trillidium (Trillium) govanianum provides an unresolved problem: morphologically it is included within Parideae, but molecular data place it within Trillium as sister to T. undulatum. Within tribe Trillieae, clades are …
Phylogenetic Relationships In Phoradendreae (Viscaceae) Inferred From Three Regions Of The Nuclear Ribosomal Cistron. Ii. The North American Species Of Phoradendron, Vanessa E. T. M. Ashworth
Phylogenetic Relationships In Phoradendreae (Viscaceae) Inferred From Three Regions Of The Nuclear Ribosomal Cistron. Ii. The North American Species Of Phoradendron, Vanessa E. T. M. Ashworth
Aliso: A Journal of Systematic and Floristic Botany
A parsimony analysis based on sequences from the ITS region and two partitions of the 26S subunit of nuclear ribosomal DNA was used to infer phylogenetic relationships among the North American species of Phoradendron. A strongly supported clade united all but one of the species typically lacking cataphylls, a character used previously to distinguish the northern species from those of Central and South America. The divergent placement of P. californicum relative to the members of this "northern" clade confirmed the hypothesis that species lacking cataphylls are polyphyletic. Four of five species parasitic on conifers formed a well-supported clade. However, a …
A Phylogenetic Classification Of Polemoniaceae, J. Mark Porter, Leigh A. Johnson
A Phylogenetic Classification Of Polemoniaceae, J. Mark Porter, Leigh A. Johnson
Aliso: A Journal of Systematic and Floristic Botany
Three hundred seventy nine species of Polemoniaceae are arranged in a phylogenetic classification composed of three subfamilies, eight tribes, and 26 genera. Nomenclature of one tribe is clarified and the circumscription of several tribes differs greatly from previous classifications. Five new genera, Bryantiella, Dayia, Lathrocasis, Microgilia, and Saltugilia, are proposed. In addition, four new species are described from the genera Allophyllum, Dayia, Giliastrum, and lpomopsis. This treatment represents a major reclassification with 59 new combinations, and the application of several additional combinations not used in recent years.
Potential Utility Of Chloroplast Trnl (Uaa) Gene Intron Sequences For Inferring Phylogeny In Scrophulariaceae, C. Edward Freeman, Ron Scogin
Potential Utility Of Chloroplast Trnl (Uaa) Gene Intron Sequences For Inferring Phylogeny In Scrophulariaceae, C. Edward Freeman, Ron Scogin
Aliso: A Journal of Systematic and Floristic Botany
Whereas chloroplast DNA-derived sequence data from protein coding regions have been utilized successfully at many taxonomic levels in recent years, sequences which are variable enough to allow for efficient phylogenetic inference (maximum information with relatively low sequencing costs and effort) at the subfamilial level huve been few. Sequence data were obtained in this study from a noncoding region, the trnL (UAA) gene intron, from a selection of taxa from the Scrophulariaceae and closely related families (representing 41 species in 26 genera). Groups of species from commonly recognized tribes and subtribes were included to determine if these taxa were grouped together …
Glume Absence In The Orcuttieae (Gramineae: Chloridoideae) And A Hypothisis Of Intratribal Relationships, Eric H. Roalson
Glume Absence In The Orcuttieae (Gramineae: Chloridoideae) And A Hypothisis Of Intratribal Relationships, Eric H. Roalson
Aliso: A Journal of Systematic and Floristic Botany
This study addresses glume absence in tribe Orcuttieae. In Orcuttia califomica, O. inaequalis, and O. viscida, all spikelets possess two glumes except for the terminal spikelet of the inflorescence, which lacks both glumes. In O. pilosa and Tuctoria greenei the terminal spikelet lacks only the first (proximal) glume, whereas in O. tenuis, T. fragilis, and T. mucronata both glumes are developed on all spikelets. This is the first report of glume absence in species of Orcuttieae other than Neostapfia colusana, which has been long reported to lack both glumes on all spikelets. A hypothesis …
Phylogeny And Adaptation In The Encelia Alliance (Asteraceae: Helliantheae), Curtis Clark
Phylogeny And Adaptation In The Encelia Alliance (Asteraceae: Helliantheae), Curtis Clark
Aliso: A Journal of Systematic and Floristic Botany
The three related genera Encelia, Enceliopsis, and Geraea comprise the alliance. The first consists primarily of shrubs and the latter two of herbaceous perennials and an annual. With the exception of two Encelia species of arid South America, all inhabit southwestern North America. Enceliopsis and Geraea are sister groups, and together form the sister group to Encelia, which includes two major clades. Especially in Encelia, there are diverse morphologies and a variety of ecological strategies marked by differences in habitat, vestiture, water balance, and photosynthetic parameters. The North American species of all three genera are obligate …
A Coalescent Approach To Chloroplast Genome Relationships Within And Between Populations Of Pinus Devoniana In Mexico, Jennifer A. Matos
A Coalescent Approach To Chloroplast Genome Relationships Within And Between Populations Of Pinus Devoniana In Mexico, Jennifer A. Matos
Aliso: A Journal of Systematic and Floristic Botany
Pinus devoniana, a member of the Pinus montezumae complex (Ponderosae) of Mexico and Central America occurs as scattered populations from the western states of Jalisco and Nayarit to Chiapas in the east. Populations within regions, i.e., western or eastern Mexico, are separated by from 75 to 300 km, while the eastern and western populations are more that 700 km apart. Levels of gene flow between populations within regions and between eastern and western Mexico are assessed using the paternally inherited chloroplast genome as a marker. Twenty-five polymorphic restriction chloroplast sites were found in the 175 individuals surveyed; …
Cladistic Parsimony Analysis Of Internal Transcribed Spacer Region (Nrdna) Sequences Of Bouteloua And Relatives (Gramineae: Chloridoideae), J. Travis Columbus, Michael S. Kinney, Rashmi Pant, Maria Elena Siqueros Delgado
Cladistic Parsimony Analysis Of Internal Transcribed Spacer Region (Nrdna) Sequences Of Bouteloua And Relatives (Gramineae: Chloridoideae), J. Travis Columbus, Michael S. Kinney, Rashmi Pant, Maria Elena Siqueros Delgado
Aliso: A Journal of Systematic and Floristic Botany
Chloridoideae) employing cladistic parsimony analysis of nuclear ribosomal internal transcribed spacer region (ITS1 + 5.8S + ITS2) DNA sequences. Included were Aegopogon (2 of 4 species), Bouteloua (34 of 42), Buchloë (1 of 1), Buchlomimus (1 of 1), Cathestecum (2 of 4), Cyclostachya (1 of 1), Griffithsochloa (1 of 1), Hilaria (1 of 7), Opizia (2 of 2), Pentarrhaphis (2 of 3), Pleuraphis (2 of 3), Pringleochloa (1 of 1), Soderstromia (1 of 1), and five outgroup genera/species for a total of I8 genera, 56 species, and ten varieties. In all, the ITS region of 72 plants was sequenced and …
Phylogeny Of Polemoniaceae Based On Nuclear Ribosomal Internal Transcribed Spacer Dna Sequences, J. Mark Porter
Phylogeny Of Polemoniaceae Based On Nuclear Ribosomal Internal Transcribed Spacer Dna Sequences, J. Mark Porter
Aliso: A Journal of Systematic and Floristic Botany
Nuclear ribosomal internal transcribed spacer (ITS) DNA sequences are used to estimate the phylogeny of 53 members of Polemoniaceae, representing all but two genera of the family. Fitch parsimony analysis of equal-weighted nucleotide sites result in 1080 minimal-length trees. However, when alignment-ambiguous positions are removed and an II: 10 transition to transversion weighting is imposed only eight trees are found. These data are used to address two issues: I) patterns of diversification in Polemoniaceae, and 2) the circumscription and monophyly of the genus Gilia. Although the monophyly of Polemoniaceae is well supported, relationships inferred among the earliest diverging lineages …
Classification: More Than Just Branching Patterns Of Evolution, Tod F. Stuessy
Classification: More Than Just Branching Patterns Of Evolution, Tod F. Stuessy
Aliso: A Journal of Systematic and Floristic Botany
The past 35 years in biological systematics have been a time of remarkable philosophical and methodological developments. For nearly a century after Darwin's Origin of Species, systematists worked to understand the diversity of nature based on evolutionary relationships. Numerous concepts were presented and elaborated upon, such as homology, parallelism, divergence, primitiveness and advancedness, cladogenesis and anagenesis. Classifications were based solidly on phylogenetic concepts; they were avowedly monophyletic. Phenetics emphasized the immense challenges represented by phylogeny reconstruction and advised against basing classifications upon it. Pheneticists forced reevaluation of all previous classificatory efforts, and objectivity and repeatability in both grouping and …
The Linnaean Hierarchy And The Evolutionization Of Taxonomy, With Emphasis On The Problem Of Nomenclature, Kevin De Queiroz
The Linnaean Hierarchy And The Evolutionization Of Taxonomy, With Emphasis On The Problem Of Nomenclature, Kevin De Queiroz
Aliso: A Journal of Systematic and Floristic Botany
During the post-Darwinian history of taxonomy, the Linnaean hierarchy has maintained its role as a means for representing hierarchical taxonomic relationships. During the same period, the principle of descent has taken on an increasingly important role as the basis for reformulated versions of fundamental taxonomic concepts and principles. Early in this history, the principle of descent provided an explanation for the existence of taxa and implied a nested, hierarchical structure for taxonomic relationships. Although an evolutionary explanation for taxa contradicted the Aristotelian context within which the Linnaean hierarchy was developed, the nested, hierarchical structure of taxonomic rela· tionships implied by …
Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan
Does The Monocot Mode Of Leaf Development Characterize All Monocots?, Geeta Bharathan
Aliso: A Journal of Systematic and Floristic Botany
Patterns of early leaf development in monocots are analyzed in a phylogenetic context. Recent developmental and phylogenetic studies enable this reevaluation of the leaf base model of the developing monocot leaf. Two questions are addressed: a) is the presence of the Vorläuferspitze (fore-runner tip) invariably correlated with development of the lamina from the lower leaf zone? and b) was the ancestral monocot characterized by the leaf base mode of development? Scanning electron microscopic observations are made of young primorida using the mold and cast method. These data are combined with data from the literature and examined in a phylogenetic context …
An Updated Phylogenetic Classification Of The Flowering Plants, Robert F. Thorne
An Updated Phylogenetic Classification Of The Flowering Plants, Robert F. Thorne
Aliso: A Journal of Systematic and Floristic Botany
This update of my classification of the flowering plants, or Angiospermae, is based upon about 800 pertinent books, monographs, and other botanical papers published since my last synopsis appeared in the Nordic Journal of Science in 1983. Also I have narrowed my family- and ordinal-gap concepts to bring acceptance of family and ordinal limits more in line with those of current taxonomists. This new information and the shift in my phylogenetic philosophy have caused significant changes in my interpretation of relationships and numbers and content of taxa. Also the ending "-anae" has been accepted for superorders in place in the …
Osmophores, Floral Features, And Systematics Of Stanhopea (Orchidaceae), Kenneth J. Curry, Lorraine M. Mcdowell, Walter S. Judd, William Louis Stern
Osmophores, Floral Features, And Systematics Of Stanhopea (Orchidaceae), Kenneth J. Curry, Lorraine M. Mcdowell, Walter S. Judd, William Louis Stern
Faculty Publications
The floral fragrance glands (osmophores) of 18 species of Stanhopea and Sievekingia were examined through a series of developmental studies at light and electron microscope levels including late bud stages through postanthesis. Various characters were identified to be of potential systematic value and were recorded for each species. These characters included: texture of the osmophore surface, number of distinct cell layers comprising the osmophore, nature of lipid inclusions in osmophore cells, and presence or absence of plastoglobuli in osmophore amyloplasts. These characters were combined with traditional features of floral lip morphology for cladistic analysis. Sievekingia was the postulated outgroup. Stanhopea …
Parallelism, It's Evolutionary Origin And Systematic Significance, K. Kubitzki, P. Von Sengbusch, H. Poppendieck
Parallelism, It's Evolutionary Origin And Systematic Significance, K. Kubitzki, P. Von Sengbusch, H. Poppendieck
Aliso: A Journal of Systematic and Floristic Botany
Parallelism as one of the forms of biological similarity is investigated in the light of recent findings from developmental and molecular biology. From the organismic point of view, functional constraints and evolutionary canalization are well established as causes of parallelism. To these may be added, from the molecular perspective, (a) erratic activations of repressed genes; (b) activations of alternative pathways under the influence ofhomoeotic genes; and (c) horizontal gene transfer, for which a simple mechanism is proposed. The control of gene expression through the action oftransposable elements, reversible to some degree, appears to be an evolutionarily important and frequent phenomenon, …
Trends In Pollination Biology, Herbert G. Baker
Trends In Pollination Biology, Herbert G. Baker
Aliso: A Journal of Systematic and Floristic Botany
An effusion of books and articles on pollination biology has appeared recently, showing a renewed interest in this area of reproductive biology that has strong significance for the continuous evolution of seed plants. Consequently, a comprehensive review is not possible in this paper; topics have been selected and a restricted number of examples given. New findings in "classical" pollination scenarios are reported, while newer topics include the chemistry of nectar in relation to phylogeny and pollinator types. The formation of "pollination ecotypes" within species is considered but the obstructive influence of "phylogenetic constraint" on close adaptation between flower and pollinator …