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A Comparison And Combination Of Plastid Atpb And Rbcl Gene Sequences For Inferring Phylogenetic Relationships Within Orchidaceae, Kenneth M. Cameron Jan 2006

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 …


The Good, The Bad, The Ugly: Using Naturally Occurring Terata To Distinguish The Possible From The Impossible In Orchid Floral Evolution, Richard M. Bateman, Paula J. Rudall Jan 2006

The Good, The Bad, The Ugly: Using Naturally Occurring Terata To Distinguish The Possible From The Impossible In Orchid Floral Evolution, Richard M. Bateman, Paula J. Rudall

Aliso: A Journal of Systematic and Floristic Botany

We interpret extensive field observations of terata in the context of recent insights into monocot phylogeny and evolutionary-developmental genetics to explore the evolution of the orchid flower. Our arguably typological classification of floral terata focuses on natural occurrences of three contrasting modes of peloria (restoration of actinomorphy in a formerly zygomorphic perianth) and three contrasting modes of pseudopeloria (lessening of the degree of zygomorphy shown by the evolutionarily preceding perianth). Dynamic evolutionary transitions in floral morphology are assigned to recently revised concepts of heterotopy (including homeosis: evolutionary transitions in position of expression) and heterochrony (evolutionary transitions in timing of expression), …


A Molecular Phylogenetic Study Of Generic And Subgeneric Relationships In The Southwest Australian Endemics Conostylis And Blancoa (Haemodoraceae), Stephen D. Hopper, Mark W. Chase, Michael F. Fay Jan 2006

A Molecular Phylogenetic Study Of Generic And Subgeneric Relationships In The Southwest Australian Endemics Conostylis And Blancoa (Haemodoraceae), Stephen D. Hopper, Mark W. Chase, Michael F. Fay

Aliso: A Journal of Systematic and Floristic Botany

We sequenced the plastid gene matK and the nuclear ribosomal spacer ITS for 39 of the 47+ species of Conostylis as well as its monotypic sister genus Blancoa, which some authors have included within Conostylis. Conostylis received 99% bootstrap support as monophyletic, with 100% support that Blancoa is its sister. Within Conostylis, the study provides strong support for two large sister clades, which we refer to as clades A (100%) and B (99%). Clade A consists of C. subgen. Conostylis plus the recently discovered C. glabra of C. subgen. Pendula sect. Divaricata (100%), and C. subgen. Pendula sect. Appendicula (100%). …


Phylogenetics Of Liliales, Michael F. Fay, Mark W. Chase, Nina Rønsted, Dion S. Devey, Yohan Pillon, J. Chris Pires, Gitte Peterson, Ole Seberg, Jerrold I. Davis Jan 2006

Phylogenetics Of Liliales, Michael F. Fay, Mark W. Chase, Nina Rønsted, Dion S. Devey, Yohan Pillon, J. Chris Pires, Gitte Peterson, Ole Seberg, Jerrold I. Davis

Aliso: A Journal of Systematic and Floristic Botany

In order to investigate interfamilial relationships of Liliales we analyzed a combined matrix of plastid rbcL, trnL intron, trnL-F intergenic spacer, matK, and ndhF, and mitochondrial atp1 DNA sequences. The results are generally congruent with previous broad analyses and provide higher bootstrap support for many relationships. Important changes relative to previous studies are the recognition of Petermanniaceae distinct from Colchicaceae and the tentative inclusion of Corsiaceae in the order. This brings the number of families in the order from nine to eleven. The additional data presented here strengthen the case for including Uvulariaceae in …


Species Boundaries And Population Divergence In The Pyrenean Endemic Relict Genus Borderea (Dioscoreaceae) As Revealed By Microsatellite (Ssr) And Other Hypervariable Markers, José Gabriel Segarra-Moragues, Pilar Catalan Jan 2006

Species Boundaries And Population Divergence In The Pyrenean Endemic Relict Genus Borderea (Dioscoreaceae) As Revealed By Microsatellite (Ssr) And Other Hypervariable Markers, José Gabriel Segarra-Moragues, Pilar Catalan

Aliso: A Journal of Systematic and Floristic Botany

Microsatellite alleles were used to delimit the genetic boundaries and divergence of the two relictual endemic Pyrenean taxa Borderea chouardii and B. pyrenaica (Dioscoreaceae), and to infer the different life histories followed by each species. Our study was conducted on the same populations previously analyzed with allozymes and RAPD markers. The three studied data sets were congruent in the inference of a single evolutionary scenario for the split of the two Borderea taxa from a common Tertiary ancestor in the Prepyrenees, thus supporting their taxonomic treatment as separate species. However, the more variable SSR and RAPD data provided better resolution …


A Synopsis Of Melanthiaceae (Liliales) With Focus On Character Evolution In Tribe Melanthieae, Wendy B. Zomlefer, Walter S. Judd, W. Mark Whitten, Norris H. Williams Jan 2006

A Synopsis Of Melanthiaceae (Liliales) With Focus On Character Evolution In Tribe Melanthieae, Wendy B. Zomlefer, Walter S. Judd, W. Mark Whitten, Norris H. Williams

Aliso: A Journal of Systematic and Floristic Botany

Melanthiaceae s.l. comprises five tribes: Chionographideae, Heloniadeae, Melanthieae, Parideae, and Xerophylleae—each defined by distinctive autapomorphies. The most morphologically diverse tribe Melanthieae, now with seven genera, had not been subject to rigorous phylogenetic character study prior to the current series of investigations that also include an overview of the family. Data from our publications and studies underway are here assessed and integrated, providing a useful overview of Melanthiaceae, and especially of Melanthieae. The results of parsimony analyses of ITS (nuclear ribosomal) and trnL-F (plastid) DNA sequence data correlate with potentially synapomorphic phenotypic characters for genera of Melanthieae, including habit form, …


Phylogenetic Analyses And Biogeography Of Trilliaceae, Susan B. Farmer Jan 2006

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 …


Population Demography And Herbivory Of Trillium Grandiflorum, Thomas P. Rooney, Kendra C. Millam Jan 2006

Population Demography And Herbivory Of Trillium Grandiflorum, Thomas P. Rooney, Kendra C. Millam

Aliso: A Journal of Systematic and Floristic Botany

Numerous pedicellate and sessile Trillium species are endemic to eastern North America, where white-tailed deer (Odocoileus virginianus) populations have been growing in recent decades. Deer feed on Trillium plants, and because they often consume all leaves and flowers, the photosynthetic capacity of browsed plants is greatly diminished. To determine if deer can influence Trillium population dynamics, we review two recent studies that applied matrix population models to understand how deer browsing affects Trillium grandijlorum. Research conducted in the Great Lakes region indicated Trillium populations in which 6-12% plants were browsed declined 3.6% per year. Simulations show that …


A Nuclear Rdna Phylogeny Of Smilax (Smilacaceae), Kenneth M. Cameron, Chengxin Fu Jan 2006

A Nuclear Rdna Phylogeny Of Smilax (Smilacaceae), Kenneth M. Cameron, Chengxin Fu

Aliso: A Journal of Systematic and Floristic Botany

Smilacaceae are a taxonomically confused, cosmopolitan family of Liliales characterized by climbing habit, reticulate leaf venation, paired petiolar tendrils, unisexual flowers, and superior ovaries. Deviations from this generalized morphology have led to the division of Smilacaceae into at least seven different genera and five sections within the large genus Smilax. In particular, taxa with connate tepals (Heterosmilax), more than six stamens (Pleiosmilax, Oligosmilax), or herbaceous habit (Hemexia) have been variously classified. Using DNA sequences of 96 taxa from the nuclear rDNA ITS gene region, parsimony analyses provide moderate resolution, but generally poor bootstrap support …


The Evolutionary And Biogeographic Origin And Diversification Of The Tropical Monocot Order Zingiberales, W. John Kress, Chelsea D. Specht Jan 2006

The Evolutionary And Biogeographic Origin And Diversification Of The Tropical Monocot Order Zingiberales, W. John Kress, Chelsea D. Specht

Aliso: A Journal of Systematic and Floristic Botany

Zingiberales are a primarily tropical lineage of monocots. The current pantropical distribution of the order suggests an historical Gondwanan distribution, however the evolutionary history of the group has never been analyzed in a temporal context to test if the order is old enough to attribute its current distribution to vicariance mediated by the break-up of the supercontinent. Based on a phylogeny derived from morphological and molecular characters, we develop a hypothesis for the spatial and temporal evolution of Zingiberales using Dispersal-Vicariance Analysis (DIVA) combined with a local molecular clock technique that enables the simultaneous analysis of multiple gene loci with …


Missing Links Between Disjunct Populations Of Androcymbium (Colchicaceae) In Africa Using Chloroplast Dna Noncoding Sequences, Alberto Del Hoyo, Joan Pedrola-Monfort Jan 2006

Missing Links Between Disjunct Populations Of Androcymbium (Colchicaceae) In Africa Using Chloroplast Dna Noncoding Sequences, Alberto Del Hoyo, Joan Pedrola-Monfort

Aliso: A Journal of Systematic and Floristic Botany

With the objective of clarifying some aspects of the biogeography, phylogeny, and taxonomy of the genus Androcymbium, we sequenced three chloroplastic DNA noncoding regions (trnL intron, trnL-trnF IGS, and trnY-trnD IGS). These data were analyzed with maximum parsimony and the ancestral areas methods following Bremer. Results show that Androcymbium is not monophyletic and that the origin of its distribution and speciation is situated in western South Africa. Later, it dispersed to North Africa, going first to eastern South Africa. Androcymbium austrocapense and A. roseum allow us to phylogenetically connect the species of …


Gondwanan Vicariance Or Dispersal In The Tropics? The Biogeographic History Of The Tropical Monocot Family Costaceae (Zingiberales), Chelsea D. Specht Jan 2006

Gondwanan Vicariance Or Dispersal In The Tropics? The Biogeographic History Of The Tropical Monocot Family Costaceae (Zingiberales), Chelsea D. Specht

Aliso: A Journal of Systematic and Floristic Botany

Costaceae are a pantropical family, distinguished from other families within the order Zingiberales by their spiral phyllotaxy and showy labellum comprised of five fused staminodes. While the majority of Costaceae species are found in the neotropics, the pantropical distribution of the family as a whole could be due to a number of historical biogeographic scenarios, including continental-drift mediated vicariance and long-distance dispersal events. Here, the hypothesis of an ancient Gondwanan distribution followed by vicariance via continental drift as the leading cause of the current pantropical distribution of Costaceae is tested, using molecular dating of cladogenic events combined with phylogeny-based biogeographic …


Robust Inference Of Monocot Deep Phylogeny Using An Expanded Multigene Plastid Data Set, Sean W. Grahan, Jessie M. Zgurski, Marc A. Mcpherson, Donna M. Cherniawsky, Jeffery M. Saarela, Elvira F. C. Horne, Selena Y. Smith, Winson A. Young, Heath E. O'Brien, Vincent L. Brown, J. Chris Pires, Richard G. Olmstead, Mark W. Chase, Hardeep S. Rai Jan 2006

Robust Inference Of Monocot Deep Phylogeny Using An Expanded Multigene Plastid Data Set, Sean W. Grahan, Jessie M. Zgurski, Marc A. Mcpherson, Donna M. Cherniawsky, Jeffery M. Saarela, Elvira F. C. Horne, Selena Y. Smith, Winson A. Young, Heath E. O'Brien, Vincent L. Brown, J. Chris Pires, Richard G. Olmstead, Mark W. Chase, Hardeep S. Rai

Aliso: A Journal of Systematic and Floristic Botany

We use multiple photosynthetic, chlororespiratory, and plastid translation apparatus loci and their associated noncoding regions (ca. 16 kb per taxon, prior to alignment) to make strongly supported inferences of the deep internal branches of monocot phylogeny. Most monocot relationships are robust (an average of ca. 91 % bootstrap support per branch examined), including those poorly supported or unresolved in other studies. Our data strongly support a sister-group relationship between Asparagales and the commelinid monocots, the inclusion of the orchids in Asparagales, and the status of Petrosaviaceae as the sister group of all monocots except Acorus and Alismatales. The latter finding …


Gondwanan Origin Of Major Monocot Groups Inferred From Dispersal-Vicariance Analysis, Kåre Bremer, Thomas Janssen Jan 2006

Gondwanan Origin Of Major Monocot Groups Inferred From Dispersal-Vicariance Analysis, Kåre Bremer, Thomas Janssen

Aliso: A Journal of Systematic and Floristic Botany

Historical biogeography of major monocot groups was investigated by biogeographical analysis of a dated phylogeny including 79 of the 81 monocot families using the Angiosperm Phylogeny Group II (APG II) classification. Five major areas were used to describe the family distributions: Eurasia, North America, South America, Africa including Madagascar, and Australasia including New Guinea, New Caledonia, and New Zealand. In order to investigate the possible correspondence with continental breakup, the tree with its terminal distributions was fitted to the geological area cladogram ((Eurasia, North America), (Africa, (South America, Australasia)) and to alternative area cladograms using the TreeFitter program. The results …


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 Jan 2006

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 …


Multigene Analyses Of Monocot Relationships, Mark W. Chase, Michael F. Fay, Dion S. Devey, Oliver Maurin, Nina Rønsted, T. Jonathan Davies, Yohan Pillon, Gitte Peterson, Minoru N. Tamura, Conny B. Asmussen, Khidir Hilu, Thomas Borsch, Jerrold I. Davis, Dennis W. Stevenson, J. Chris Pires, Thomas J. Givnish, Kenneth J. Systma, Marc A. Mcpherson, Sean W. Graham, Hardeep S. Rai Jan 2006

Multigene Analyses Of Monocot Relationships, Mark W. Chase, Michael F. Fay, Dion S. Devey, Oliver Maurin, Nina Rønsted, T. Jonathan Davies, Yohan Pillon, Gitte Peterson, Minoru N. Tamura, Conny B. Asmussen, Khidir Hilu, Thomas Borsch, Jerrold I. Davis, Dennis W. Stevenson, J. Chris Pires, Thomas J. Givnish, Kenneth J. Systma, Marc A. Mcpherson, Sean W. Graham, Hardeep S. Rai

Aliso: A Journal of Systematic and Floristic Botany

We present an analysis of supra-familial relationships of monocots based on a combined matrix of nuclear I8S and partial 26S rDNA, plastid atpB, matK, ndhF, and rbcL, and mitochondrial atp1 DNA sequences. Results are highly congruent with previous analyses and provide higher bootstrap support for nearly all relationships than in previously published analyses. Important changes to the results of previous work are a well-supported position of Petrosaviaceae as sister to all monocots above Acorales and Alismatales and much higher support for the commelinid clade. For the first time, the spine of the monocot tree has …


Placing The Monocots: Conflicting Signal From Trigenomic Analyses, Melvin R. Duvall, Sarah Matthews, Neill Mohammad, Tammy Russel Jan 2006

Placing The Monocots: Conflicting Signal From Trigenomic Analyses, Melvin R. Duvall, Sarah Matthews, Neill Mohammad, Tammy Russel

Aliso: A Journal of Systematic and Floristic Botany

Despite recent significant advances in understanding angiosperm phylogeny, the position of monocots remains uncertain. We present here a phylogeny inferred from four genes that unambiguously unite monocots with eumagnoliids. A well-supported position for the monocots was obtained only after we replaced the available nuclear 18S rDNA sequence data with data from phytochrome C in a matrix that also included plastid rbcL and ndhF and mitochondrial atp1. Over 5000 base pairs of sequence data from 42 taxa were analyzed using Bayesian inference. The results of these analyses united monocots with the eumagnoliids in a well-supported clade. Although the …


The Fossil Record Of Basal Monocots, Ruth A. Stockey Jan 2006

The Fossil Record Of Basal Monocots, Ruth A. Stockey

Aliso: A Journal of Systematic and Floristic Botany

The fossil record of basal monocots (Acorales and Alismatales) extends back to the Cretaceous in the Northern Hemisphere. While many fossils were originally assigned to these basal groups, rigorous paleobotanical studies show many of them to be misidentified. Acarus fossils have been reliably reported from the Eocene while those of Alismatales extend back to the early Cretaceous. The fossil record of basal monocots is usually represented by leaves, fruits, and seeds; however, some localities preserve stems with attached leaves and roots and even whole plants. A detailed examination of leaf venation patterns in alismatids has recently allowed the description of …


Vegatative Architecture Of Desiccation-Tolerant Arborescent Monocotyledons, Stefan Porembski Jan 2006

Vegatative Architecture Of Desiccation-Tolerant Arborescent Monocotyledons, Stefan Porembski

Aliso: A Journal of Systematic and Floristic Botany

Within the monocotyledons the acquisition of the tree habit is enhanced by either primary growth of the axis or a distinctive mode of secondary growth. However, a few arborescent monocotyledons deviate from this pattern in developing trunks up to four meters high that resemble those of tree ferns, i.e., their "woody-fibrous" stems consist mainly of persistent leaf bases and adventitious roots. This type of arborescent monocotyledon occurs in both tropical and temperate regions and is found within Boryaceae (Borya), Cyperaceae (Afrotrilepis, Bulbostylis, Coleochloa, Microdracoides), and Velloziaceae (e.g., Vellozia, Xerophyta). They have developed in geographically widely separated regions …


Perianth Development In The Basal Monocot Triglochin Maritima (Juncaginaceae), Matyas Buzgo, Douglas E. Soltis, Pamela S. Soltis, Sangtae Kim, Hong Ma, Bernard A. Hauser, Jim Lebens-Mack, Bo Johansen Jan 2006

Perianth Development In The Basal Monocot Triglochin Maritima (Juncaginaceae), Matyas Buzgo, Douglas E. Soltis, Pamela S. Soltis, Sangtae Kim, Hong Ma, Bernard A. Hauser, Jim Lebens-Mack, Bo Johansen

Aliso: A Journal of Systematic and Floristic Botany

Basal monocots exhibit considerable variation in inflorescence and floral structure. In some cases, such as Triglochin maritima, it is not clear whether the lateral and terminal structures of the inflorescence are flowers or pseudanthia, or where the limits between flowers and inflorescence lie. To address these questions, morphological studies were carried out, and the results show that in T. maritima both terminal and lateral structures are flowers, not pseudanthia. The terminal flower of T. maritima develops from the apical inflorescence meristem, suggesting that the apical meristem identity changes from "inflorescence" to "flower" during inflorescence development. In addition, distal flowers …


Fleshy Fruits In Liliflorous Monocots, Finn N. Rasmussen, Signe Frederikson, Bo Johansen, Lise Bolt Jørgenson, Gitte Peterson Jan 2006

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 …


Molecular Basis Of Development In Petaloid Monocot Flowers, Bo Johansen, Signe Frederikson Jan 2006

Molecular Basis Of Development In Petaloid Monocot Flowers, Bo Johansen, Signe Frederikson

Aliso: A Journal of Systematic and Floristic Botany

and several studies have confirmed the extended ABC model as the molecular background of flower development in this plant group. The core eudicots are characterized as having one copy of each of the B-class genes and at least two copies of A-class genes: one is expressed in floral meristems, the other in inflorescence meristems. In monocots and non-core eudicots the validity of the ABC model is under discussion. Generally, more than one functional copy is found of at least one of the B-class genes. The A-class genes apparently are expressed in meristems of both flower and inflorescence. Morphologically petaloid stamens …


Patterns Of Floral Structure And Orientation In Japonolirion , Narthecium, And Tofieldia, Margarita V. Remizowa, Dmitry D. Sokoloff, Paula J. Rudall Jan 2006

Patterns Of Floral Structure And Orientation In Japonolirion , Narthecium, And Tofieldia, Margarita V. Remizowa, Dmitry D. Sokoloff, Paula J. Rudall

Aliso: A Journal of Systematic and Floristic Botany

Floral evolution requires reassessment in basal monocots, including species formerly assigned to Melanthiaceae, in the light of recent developments in the molecular phylogenetics of monocots. We have investigated flowers of Tofieldia (Tofieldiaceae), Japonolirion (Petrosaviaceae), and Narthecium (Nartheciaceae). We confirm Engler's (1888) hypothesis that orientation of lateral flowers in monocots is dependent on presence and position of additional phyllomes on the pedicel. The type of floral orientation that occurs in Tofieldia is unusual for monocots, since the additional phyllomes are represented by calyculus scales rather than a bracteole, and the outer whorl tepals are initiated alternating with the calyculus scales. In …


Recommendations And Goals For Evo-Devo Research, Michael J. Frohlich Jan 2006

Recommendations And Goals For Evo-Devo Research, Michael J. Frohlich

Aliso: A Journal of Systematic and Floristic Botany

The rapidly growing field of evolutionary-developmental biology (evo-devo) arises from the fusion of formerly disjunct scientific disciplines that traditionally generate very different scientific products. What should the scientific product of evo-devo be? I propose it should be a testable evolutionary scenario. Evolutionary scenarios have suffered eclipse and even opprobrium in recent years, but analysis of genes that control development may make evo-devo scenarios testable, hence scientifically valid. Hypothesis-based studies are more likely than descriptive studies to generate testable evolutionary scenarios. Candidate-gene studies are risky if only one or a few genes are known in the pathway that is putatively responsible …


The Operculum In Pollen Of Monocotyledons, Carol A. Furness, Paula J. Rudall Jan 2006

The Operculum In Pollen Of Monocotyledons, Carol A. Furness, Paula J. Rudall

Aliso: A Journal of Systematic and Floristic Botany

Within monocotyledons, monosulcate pollen is the predominant type and probably represents the plesiomorphic condition, but considerable variation occurs in sulcus morphology. An operculum is an exine thickening that covers most of an aperture. Monocot opercula are usually associated with sulci, although they can occur in ulcerate apertures, as in Poaceae. There are several other aperture types closely related to the monosulcate-operculate type, and confusion occurs in the palynological literature between monosulcate-operculate, pontoperculate, disulculate, disulcate, and zona-aperturate (zonasulculate or zonasulcate) pollen. Transmission electron microscopy (TEM) was used to determine the distribution of the thick apertural intine and to accurately identify these …


A Reappraisal Of Phylogentic Relationships In The Monocotyledon Family Hydrocharitaceae (Alismatidae), Donald H. Les, Michael L. Moody, Connie L. Soros Jan 2006

A Reappraisal Of Phylogentic Relationships In The Monocotyledon Family Hydrocharitaceae (Alismatidae), Donald H. Les, Michael L. Moody, Connie L. Soros

Aliso: A Journal of Systematic and Floristic Botany

The diverse, aquatic Hydrocharitaceae have defied stable classification for nearly two centuries. Anatomical and morphological convergence characterize many aquatic plants and undoubtedly have hindered the ability of researchers to ascertain accurately those features representing reliable phylogenetic markers within Hydrocharitaceae. Most prior classifications of the family have emphasized few characters to define major taxonomic subdivisions (i.e., they were highly artificial). Previous studies using molecular data have shown that DNA sequences provide novel indications of phylogeny not indicated previously by morphologically based classifications; however, they have not yet recommended alterations to the classification for the family. We conducted a more comprehensive phylogenetic …


Speciation In Duckweeds (Lemnaceae): Phylogenetic And Ecological Inferences, Daniel J. Crawford, Elias Landolt, Donald H. Les, Rebecca T. Kimball Jan 2006

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; …


Pollen Wall Ultrastructure Of Araceae And Lemnaceae In Relation To Molecular Classifications, Michael Hesse Jan 2006

Pollen Wall Ultrastructure Of Araceae And Lemnaceae In Relation To Molecular Classifications, Michael Hesse

Aliso: A Journal of Systematic and Floristic Botany

A comparative ultrastructural study of Araceae pollen walls was conducted for the first time. The results are based mainly on investigations by transmission electron microscopy of 101 species in 70 genera (out of a total of 105 genera), while pollen of 83 genera with 219 species were studied by scanning electron microscopy, generally without acetolysis. Special attention was given to Lemnaceae (including Limnobiophyllum) considered to be closely related to Araceae (especially to Pistia). The ultrastructural pollen wall characters are mostly in accordance with and strongly support the morphological classifications and the arrangement of genera within recent molecular trees. …


Further Evidence For Seed Size Variation In The Genus Zostera: Exploratory Studies With Z. Japonica And Z. Asiatica, Sandy Wyllie-Echeverria, Victoria R. Wyllie-Echeverria, Algernon C. Churchill, Paul A. Cox Jan 2006

Further Evidence For Seed Size Variation In The Genus Zostera: Exploratory Studies With Z. Japonica And Z. Asiatica, Sandy Wyllie-Echeverria, Victoria R. Wyllie-Echeverria, Algernon C. Churchill, Paul A. Cox

Aliso: A Journal of Systematic and Floristic Botany

Recent studies found seed size variation within the seagrass Zostera marina, one of nine species in the genus Zostera. The objectives of this study were to determine if variation also exists in the seeds of two other species Zostera japonica and Zostera asiatica within this genus. Results indicate that: (1) length and weight varied between two populations (one indigenous population from Akkeshi-Ko, Japan, and one exotic population from Willapa Bay, Washington, USA) of the small-bodied intertidal seagrass species Z. japonica, and (2) seed-size classes were discernable. Preliminary investigations were also initiated with a Japanese population of Z. asiatica …


A Phylogenetic Study Of Arecaceae Based On Seedling Morphological And Anatomical Data, Flor M. Henderson, Dennis W. Stevenson Jan 2006

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 …