Open Access. Powered by Scholars. Published by Universities.®

Botany Commons™

Open Access. Powered by Scholars. Published by Universities.®

2006

Discipline
Institution
Keyword
Publication
Publication Type

Articles 91 - 120 of 185

Full-Text Articles in Botany

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 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 …

Go to article

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 …

Go to article

Rack1 Mediates Multiple Hormone Responsiveness And Developmental Processes In Arabidopsis, Hemayet Ullah Jan 2006

Rack1 Mediates Multiple Hormone Responsiveness And Developmental Processes In Arabidopsis, Hemayet Ullah

Department of Biology Faculty Publications

The scaffold protein RACK1 (Receptor for Activated C Kinase 1) serves as an integrative point for diverse signal transduction pathways. The Arabidopsis genome contains three RACK1 orthologues, however, little is known about their functions. It is reported here that one memberof this gene family, RACK1A, previously identified as the Arabidopsis homologue of the tobacco arcA gene, mediates hormone responses and plays a regulatory role in multiple developmental processes. RACK1A expresses ubiquitously in Arabidopsis. Loss-of-function mutations in RACK1A confer defects in multiple developmental processes including seed germination, leaf production, and flowering. rack1a mutants displayed reduced sensitivity to gibberellin and brassinosteroid in …

Go to article

2006 Vegetation Survey Of The Valentine National Wildlife Refuge, Robert F. Steinauer Jan 2006

2006 Vegetation Survey Of The Valentine National Wildlife Refuge, Robert F. Steinauer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

The Valentine National Wildlife Refuge (VNWR), located in north central Cherry County, was established in 1934. Tolstead (1942) studied the grasslands of northern Cherry County, (including the Valentine National Wildlife Refuge) with a focus on describing the dominant species of grassland types and determining the relationships between vegetation distribution and environmental variables and management practices. Additional studies have been conducted by refuge staff on the effects of management, particularly grazing, on vegetation structure. The purpose of this study was to: (1) document all vascular plant species present on the refuge; (2) collect data on rare plant species and high-quality native …

Go to article

Influence Of Nutrient Availability, Stand Age, And Canopy Structure On Isoprene Flux In A Eucalyptus Saligna Experimental Forest, Jennifer L. Funk, Christian P. Giardina, Alexander Knohl, Manuel T. Lerdau Jan 2006

Influence Of Nutrient Availability, Stand Age, And Canopy Structure On Isoprene Flux In A Eucalyptus Saligna Experimental Forest, Jennifer L. Funk, Christian P. Giardina, Alexander Knohl, Manuel T. Lerdau

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Eucalyptus plantations occupy approximately 10 million ha of land in the tropics and, increasingly, afforestation and reforestation projects are relying on this genus to provide rapid occupation of degraded sites, large quantities of high-quality wood products, and high rates of carbon sequestration. Members of the genus Eucalyptus are also very high emitters of isoprene, the dominant volatile organic compound emitted by trees in tropical ecosystems, which significantly influences the oxidative capacity of the atmosphere. While fertilization growth response of these trees has been intensively studied, little is known about how fertilization and tree age alter isoprene production from plantations of …

Go to article

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 Floristic 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, and …

Go to article

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 …

Go to article

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 …

Go to article

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

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 …

Go to article

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), …

Go to article

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, …

Go to article

Snp-Phage – High Throughput Snp Discovery Pipeline, Lakshmi K. Matukumalli, John J. Grefenstette, David L. Hyten, Ik-Young Choi, Perry B. Cregan, Curt P. Van Tassell Jan 2006

Snp-Phage – High Throughput Snp Discovery Pipeline, Lakshmi K. Matukumalli, John J. Grefenstette, David L. Hyten, Ik-Young Choi, Perry B. Cregan, Curt P. Van Tassell

Department of Agronomy and Horticulture: Faculty Publications

Background: Single nucleotide polymorphisms (SNPs) as defined here are single base sequence changes or short insertion/deletions between or within individuals of a given species. As a result of their abundance and the availability of high throughput analysis technologies SNP markers have begun to replace other traditional markers such as restriction fragment length polymorphisms (RFLPs), amplified fragment length polymorphisms (AFLPs) and simple sequence repeats (SSRs or microsatellite) markers for fine mapping and association studies in several species. For SNP discovery from chromatogram data, several bioinformatics programs have to be combined to generate an analysis pipeline. Results have to be stored in …

Go to article

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; …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

Phylogeny, Genome Size, And Chromosome Evolution Of Asparagales, J. Chris Pires, Ivan J. Maureira, Thomas J. Givnish, Kenneth J. Systma, Ole Seberg, Gitte Peterson, Jerrold I. Davis, Dennis W. Stevenson, Paula J. Rudall, Michael F. Fay, Mark W. Chase Jan 2006

Phylogeny, Genome Size, And Chromosome Evolution Of Asparagales, J. Chris Pires, Ivan J. Maureira, Thomas J. Givnish, Kenneth J. Systma, Ole Seberg, Gitte Peterson, Jerrold I. Davis, Dennis W. Stevenson, Paula J. Rudall, Michael F. Fay, Mark W. Chase

Aliso: A Journal of Systematic and Floristic Botany

Asparagales are a diverse monophyletic order that has numerous species (ca. 50% of monocots) including important crop plants such as Allium, Asparagus, and Vanilla, and a host of ornamentals such as irises, hyacinths, and orchids. Historically, Asparagales have been of interest partly because of their fascinating chromosomal evolution. We examine the evolutionary dynamics of Asparagales genomes in an updated phylogenetic framework that combines analyses of seven gene regions (atp1, atpB, matK, ndhF, rbcL, trnL intron, and trnL-F intergenic spacer) for 79 taxa of Asparagales and outgroups. Asparagales genomes are evolutionarily labile for …

Go to article

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 Floristic 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 …

Go to article

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 Floristic 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 …

Go to article

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 Floristic 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 …

Go to article

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 …

Go to article

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 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 …

Go to article

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 …

Go to article

Letter From The Dean, Gregory J. Weidemann Jan 2006

Letter From The Dean, Gregory J. Weidemann

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

No abstract provided.

Go to article

Evaluation Of The Single Kernel Characterization System (Skcs) For Measurement Of Sorghum Grain Attributes, S. R. Bean, O. K. Chung, M. R. Tuinstra, Jeffrey F. Pedersen, J. Erpelding Jan 2006

Evaluation Of The Single Kernel Characterization System (Skcs) For Measurement Of Sorghum Grain Attributes, S. R. Bean, O. K. Chung, M. R. Tuinstra, Jeffrey F. Pedersen, J. Erpelding

Department of Agronomy and Horticulture: Faculty Publications

The single kernel characterization system (SKCS) has been widely used in the wheat industry, and SKCS parameters have been linked to end-use quality in wheat. The SKCS has promise as a tool for evaluating sorghum grain quality. However, the SKCS was designed to analyze wheat, which has a different kernel structure from sorghum. To gain a better understanding of the meaning of SKCS predictions for grain sorghum, individual sorghum grains were measured for length, width, thickness (diameter), and weight by laboratory methods and by the SKCS. SKCS predictions for kernel weight and thickness were highly correlated to laboratory measurements. However, …

Go to article

Application Of Machine Learning In Snp Discovery, Lakshmi K. Matukumalli, John J. Grefenstette, David L. Hyten, Ik-Young Choi, Perry B. Cregan, Curtis P. Van Tassell Jan 2006

Application Of Machine Learning In Snp Discovery, Lakshmi K. Matukumalli, John J. Grefenstette, David L. Hyten, Ik-Young Choi, Perry B. Cregan, Curtis P. Van Tassell

Department of Agronomy and Horticulture: Faculty Publications

Background: Single nucleotide polymorphisms (SNP) constitute more than 90% of the genetic variation, and hence can account for most trait differences among individuals in a given species. Polymorphism detection software PolyBayes and PolyPhred give high false positive SNP predictions even with stringent parameter values. We developed a machine learning (ML) method to augment PolyBayes to improve its prediction accuracy. ML methods have also been successfully applied to other bioinformatics problems in predicting genes, promoters, transcription factor binding sites and protein structures. Results: The ML program C4.5 was applied to a set of features in order to build a SNP classifier …

Go to article

Prehistoric And Medieval Plant Remains From Two Sites On The Euphrates, South-Eastern Turkey, Emel Oybak Dönmez Jan 2006

Prehistoric And Medieval Plant Remains From Two Sites On The Euphrates, South-Eastern Turkey, Emel Oybak Dönmez

Turkish Journal of Botany

The results of the archaeobotanical examination of 2 sites, namely Mezraa Höyük and Gre Virike, on the Euphrates in the Karkamış (Carchemish) area, near Birecik (Şanlıurfa) in south-east Turkey are given. The cultural levels that yielded carbonised plant remains date from the Early Bronze Age (3000-2000 BC), Middle Bronze Age (2000-1500 BC) and Medieval period (11^{th} - 13^{th} centuries AD). The plant assortment in the Bronze Age did not differ essentially from that during the Medieval period. The major crop plant of the farmers was Hordeum L. (barley, hulled). Other cereal crops included Triticum dicoccum Schübl. (emmer wheat), T. monococcum …

Go to article

Morphological And Palynological Investigation On Silene Gigantea L. Var. Gigantea And Silene Behen L. (Caryophyllaceae) Distributed In Western Anatolia And Northern Cyprus, Kemal Yildiz Jan 2006

Morphological And Palynological Investigation On Silene Gigantea L. Var. Gigantea And Silene Behen L. (Caryophyllaceae) Distributed In Western Anatolia And Northern Cyprus, Kemal Yildiz

Turkish Journal of Botany

A comparative investigation was carried out on the morphology and palynology of Silene gigantea L. var. gigantea and Silene behen L. species of the family Caryophyllaceae distributed in Western Anatolia and Northern Cyprus. An examination conducted on S. gigantea var. gigantea revealed that the calyx length in Western Anatolian specimens was shorter than that of those from Northern Cyprus, that the basal petal blades of the Western Anatolian specimens did not have any ligula while those from Northern Cyprus did, and that the petal blades belonging to the specimens from Northern Cyprus demonstrated less clefting as compared to those from …

Go to article

Achillea Salicifolia Besser Subsp. Salicifolia (Asteraceae) In Turkey, With Taxonomic Remarks, Turan Arabaci, Bayram Yildiz Jan 2006

Achillea Salicifolia Besser Subsp. Salicifolia (Asteraceae) In Turkey, With Taxonomic Remarks, Turan Arabaci, Bayram Yildiz

Turkish Journal of Botany

This study includes taxonomical improvements of Achillea salicifolia Besser subsp. salicifolia and distributions in Turkey. Differences between A. salicifolia subsp. salicifolia and relatives are discussed, and synonyms are established. Furthermore, description, localities, distribution map, and key of allied species are given.

Go to article

First Prev Next Last