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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 Evolutionary 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. For example ...


Patterns In Evolution In Characters That Define Iris Subgenera And Sections, Carol A. Wilson Jan 2006

Patterns In Evolution In Characters That Define Iris Subgenera And Sections, Carol A. Wilson

Aliso: A Journal of Systematic and Evolutionary 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 ...


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 Evolutionary 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 ...


Systematics Of Xanthorrhoeaceae Sensu Lato, With An Emphasis On Bulbine, Dion S. Devey, Ilia Leitch, J. Chris Pires, Yohan Pillon, Mark W. Chase Jan 2006

Systematics Of Xanthorrhoeaceae Sensu Lato, With An Emphasis On Bulbine, Dion S. Devey, Ilia Leitch, J. Chris Pires, Yohan Pillon, Mark W. Chase

Aliso: A Journal of Systematic and Evolutionary Botany

We provide here results of a combined analysis of plastid genes rbcL, matK, and ndhF for Xanthorrhoeaceae s.l., the Asphodelaceae/Xanthorrhoeaceae/Hemerocallidaceae clade, which are well supported by the DNA data. Xanthorrhoea (often treated as the sole member of Xanthorrhoeaceae) is sister to the hemerocallid clade (former Hemerocallidaceae); and the asphodelid clade (formerly Asphodelaceae) is sister to them both. For additional species of Bulbine and Jodrellia (both Asphodeloideae), we also collected rps16 intron and ITS nuclear ribosomal DNA sequences to better assess their relationships. Bulbine, with Jodrellia, embedded are sister to the collective genera of ...


Molecular Studies Of Subfamily Gilliesioideae (Alliaceae), Michael F. Fay, Paula J. Rudall, Mark W. Chase Jan 2006

Molecular Studies Of Subfamily Gilliesioideae (Alliaceae), Michael F. Fay, Paula J. Rudall, Mark W. Chase

Aliso: A Journal of Systematic and Evolutionary Botany

We present an analysis of relationships in Gilliesioideae (Alliaceae) based on a combined matrix of plastid rbcL, the trnL intron, the trnL-F intergenic spacer, and the rps16 intron and nuclear ITS ribosomal DNA sequences. The results are generally congruent with previous analyses, indicating two well-supported groups: Ipheion plus allied genera ("lpheieae" ined.) and Gilliesieae. They also provide higher bootstrap support for many patterns of relationships. Polyphyly of lpheion and Nothoscordum is confirmed. Increased taxon sampling (particularly in Gilliesieae) and additional molecular data would be desirable to provide further resolution and to allow an appropriate taxonomic revision ...


Phylogenetics Of The "Tiger-Flower" Group (Tigridieae: Iridaceae): Molecular And Morphological Evidence, Aaron Rodriguez, Kenneth J. Sytsma Jan 2006

Phylogenetics Of The "Tiger-Flower" Group (Tigridieae: Iridaceae): Molecular And Morphological Evidence, Aaron Rodriguez, Kenneth J. Sytsma

Aliso: A Journal of Systematic and Evolutionary Botany

The phylogenetic relationships among 23 species of the tribe Tigridieae (lridaceae) were inferred using morphological data and nucleotide sequences from nuclear ITS and three intergenic spacers of the cpDNA: psbA-trnH, trnT-trnL, and trnL-trnF. Although all data sets supported a monophyletic Mexican-Guatemalan Tigridiinae including two taxa usually placed in Cipurinae (Cardiostigma longispatha and Nemastylis convoluta), neither morphology, cpDNA, nor ITS resolved phylogenetic relationships within this lineage. A graphical tree of trees analysis showed the cladograms derived from morphology to be the most topologically distinct within the set of all trees examined and ...


Phylogenetics Of Lilliales, 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 Lilliales, 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 Evolutionary 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 ...


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 Evolutionary 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 noted that correspond ...


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 Evolutionary 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 western ...


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 Evolutionary 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 large-bodied ...


Stem Anatomy Of Climbing Palms In Relation To Long-Distance Water Transport, P. Barry Tomlinson Jan 2006

Stem Anatomy Of Climbing Palms In Relation To Long-Distance Water Transport, P. Barry Tomlinson

Aliso: A Journal of Systematic and Evolutionary Botany

Palms lack secondary growth so their primary vascular system is long-lived and must be minimally vulnerable to dysfunction. For water movement, the axial xylem must be well defended against cavitation. Climbing palms can be very long and represent a maximum solution to transport problems. How is this demonstrated in their anatomy? This article contrasts stem vascular anatomy in a canelike "tree palm" (Rhapis excelsa) with that in the American climbing palm Desmoncus and the Old World rattan genus Calamus. Rhapis, representing the basic classical palm vasculature, has a continuously integrated vascular system determined by branching of the axial (stem) system ...


Genomic Resources For Asparagales, Michael J. Havey, Kenneth C. Sink, Maria Jenderek, Christopher D. Town Jan 2006

Genomic Resources For Asparagales, Michael J. Havey, Kenneth C. Sink, Maria Jenderek, Christopher D. Town

Aliso: A Journal of Systematic and Evolutionary Botany

Enormous genomic resources have been developed for plants in the monocot order Poales; however, it is not known how useful these resources will be for other economically important monocots. Asparagales are a monophyletic order sister to class Commelinanae that carries Poales, and is the second most economically important monocot order. Development of genomic resources for and their application to Asparagales are challenging because of huge nuclear genomes and the relatively long generation times required to develop segregating families. We synthesized a normalized eDNA library of onion (Allium cepa) and produced II ,008 unique expressed sequence tags (ESTs) for comparative genomic ...


Pollination Biology And Adaptive Radiation Of Agavaceae, With Special Emphasis On The Genus Agave, Martha Rocha, Sara V. Good-Ávila, Fracisco Molina-Freaner, Hector T. Arita, Amanda Castillo, Abisaí García-Mendoza, Arturo Silva-Montellano, Brandon S. Gaut, Valeria Souza, Luis E. Eguiarte Jan 2006

Pollination Biology And Adaptive Radiation Of Agavaceae, With Special Emphasis On The Genus Agave, Martha Rocha, Sara V. Good-Ávila, Fracisco Molina-Freaner, Hector T. Arita, Amanda Castillo, Abisaí García-Mendoza, Arturo Silva-Montellano, Brandon S. Gaut, Valeria Souza, Luis E. Eguiarte

Aliso: A Journal of Systematic and Evolutionary Botany

Agavaceae are an American family that comprises nine genera and ca. 300 species distributed in arid and semiarid environments, mainly in Mexico. The family is very successful and displays a wide array of ecological, reproductive, and morphological adaptations. Many of its members play important roles as keystone species, because they produce abundant resources during the reproductive season. In this paper we analyze the current knowledge about the pollination ecology of the different genera in the family and the role that pollination systems have played in the ecological and phylogenetic success of the group. After providing an overview of each of ...


The Never-Ending Story: Multigene Approaches To The Phylogeny Of Amaryllidaceae, Alan W. Meerow, Deirdre A. Snuman Jan 2006

The Never-Ending Story: Multigene Approaches To The Phylogeny Of Amaryllidaceae, Alan W. Meerow, Deirdre A. Snuman

Aliso: A Journal of Systematic and Evolutionary 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 ...


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 Jan 2006

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 Evolutionary 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 ...


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 Evolutionary 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 Evolutionary 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 ...


Subtribal Relationships In Tribe Tradescantieae (Commelinaceae)Based On Molecular And Morphological Data, Dylan J. Wade, Timothy M. Evans, Robert B. Faden Jan 2006

Subtribal Relationships In Tribe Tradescantieae (Commelinaceae)Based On Molecular And Morphological Data, Dylan J. Wade, Timothy M. Evans, Robert B. Faden

Aliso: A Journal of Systematic and Evolutionary Botany

Tribe Tradescantieae (Commelinaceae) consists of seven subtribes and 25 genera. Previous attempts to evaluate phylogenetic relationships within the group using morphology or the chloroplast-encoded rbcL have either been highly homoplasious (morphology) or provided only weak support for subtribal relationships due to insufficient variability (rbcL). In this study, phylogenetic analysis of nucleotide sequence data from the chloroplast-encoded ndhF and rbcL genes, as well as 47 morphological and anatomical characters, were used to evaluate relationships within and among the subtribes of Tradescantieae. The addition of ndhF resulted in a more highly resolved phylogeny and greater bootstrap and ...


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 Evolutionary 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 Evolutionary 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 ...


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 Evolutionary 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 for phylogenetic relationships in the family ...


Phlogeny And Biogeography Of The Prayer Plant Family, Linda M. Prince, W. John Kress Jan 2006

Phlogeny And Biogeography Of The Prayer Plant Family, Linda M. Prince, W. John Kress

Aliso: A Journal of Systematic and Evolutionary 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 ...


Phylogenetic Relationships Of Monocots Based On The Highly Informative Plastid Gene Ndhf, Thomas J. Givnish, J. Chris Pires, Sean W. Graham, Marc A. Mcpherson, Linda M. Prince, Thomas B. Patterson, Hardeep S. Rai, Eric H. Roalson, Timothy M. Evans, William J. Hahn, Kendra C. Millam, Alan W. Meerow, Mia Molvray, Paul J. Kores, Heath W. O'Brien, Jocelyn C. Hall, W. John Kress, Kenneth J. Sytsma Jan 2006

Phylogenetic Relationships Of Monocots Based On The Highly Informative Plastid Gene Ndhf, Thomas J. Givnish, J. Chris Pires, Sean W. Graham, Marc A. Mcpherson, Linda M. Prince, Thomas B. Patterson, Hardeep S. Rai, Eric H. Roalson, Timothy M. Evans, William J. Hahn, Kendra C. Millam, Alan W. Meerow, Mia Molvray, Paul J. Kores, Heath W. O'Brien, Jocelyn C. Hall, W. John Kress, Kenneth J. Sytsma

Aliso: A Journal of Systematic and Evolutionary Botany

We used ndhF sequence variation to reconstruct relationships across 282 taxa representing 78 monocot families and all 12 orders. The resulting tree is highly resolved and places commelinids sister to Asparagales, with both sister to Liliales—Pandanales in the strict consensus; Pandanales are sister to Dioscoreales in the bootstrap majority-rule tree, just above Petrosaviales. Acorales are sister to all other monocots, with Alismatales sister to all but Acorales. Relationships among the four major clades of commelinids remain unresolved. Relationships within orders are consistent with those based on rbcL, alone or in combination with atpB and 18S nrDNA ...


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 Evolutionary 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 Evolutionary 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 ...


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 Evolutionary 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 with ...


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 Evolutionary 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 Evolutionary 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 Evolutionary 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 ...


Aperture Pattern And Microsporogenesis In Asparagales, Sophie Nadot, Laurent Penet, Leanne D. Dreyer, Arlette Forchioni, Adrienne Ressayre Jan 2006

Aperture Pattern And Microsporogenesis In Asparagales, Sophie Nadot, Laurent Penet, Leanne D. Dreyer, Arlette Forchioni, Adrienne Ressayre

Aliso: A Journal of Systematic and Evolutionary Botany

The aperture pattern of pollen grains is a character defined as the number, shape, and position of apertures. Although this character is highly variable in angiosperms, two states are particularly widespread. Pollen grains with one polar aperture occur frequently in basal angiosperms and monocots while tricolpate pollen is a synapomorphy of the eudicots. Many morphological characters are the result of a compromise between selective forces (acting on morphology) and developmental constraints (limiting the range of possible morphologies). To investigate what are the respective roles of development and selection in the determination of aperture pattern in angiosperms, we have chosen to ...