Origin and relationships of Saintpaulia (Gesneriaceae) based on ribosomal DNA internal transcribed spacer (ITS) sequences.

abstract：:Because leaf pubescence of the desert shrub Encelia farinosa increases in response to drought and influences photosynthesis and transpiration, we hypothesized that differences in water availability across the range of this species may result in genetic differentiation for pubescence and associated productivity traits....

journal_title：American journal of botany

authors： Sandquist DR,Ehleringer JR

更新日期：2003-10-01 00:00:00

abstract：:The taxonomic richness of seed plants at different taxonomic levels was compared between temperate East Asia and North America at both continental and semi-continental scales. In each comparison, land area and latitude range were adjusted to a comparable level between the two continental regions. East Asia is signific...

journal_title：American journal of botany

authors： Qian H

更新日期：2002-11-01 00:00:00

abstract：:The utility of the PCR-based AFLP technique (polymerase chain reaction; amplified fragment length polymorphisms) was explored in elucidating details of polyploid evolution in the Eurasian orchid genus Dactylorhiza. We emphasized Swedish taxa but also included some material from the British Isles and elsewhere in Europ...

journal_title：American journal of botany

authors： Hedrén M,Fay MF,Chase MW

更新日期：2001-10-01 00:00:00

abstract：:Developmental and physiological studies of roots are frequently limited to a post-germination stage. In Arabidopsis, a developmental change in the root meristem architecture during plant ontogenesis has not previously been studied and is addressed presently. Arabidopsis thaliana have closed root apical organization, i...

journal_title：American journal of botany

authors： Baum SF,Dubrovsky JG,Rost TL

更新日期：2002-06-01 00:00:00

abstract：:In the alpine landscape most plant populations are spatially isolated due to extreme patchiness and strong natural fragmentation. We used RAPD-PCR (randomly amplified polymorphic DNA polymerase chain reaction) for a study of the genetic diversity within and among 20 populations of Geum reptans, an outcrossing clonal p...

journal_title：American journal of botany

authors： Pluess AR,Stöcklin J

更新日期：2004-12-01 00:00:00

abstract：:The evolutionary history of maize (Zea mays subsp. mays) is of general interest because of its economic and scientific importance. Here we show that many cellular traits described previously in developing caryopses of maize are also seen in its wild progenitor teosinte (Zea mays subsp. parviglumis). These features, ea...

journal_title：American journal of botany

authors： Dermastia M,Kladnik A,Dolenc Koce J,Chourey PS

更新日期：2009-10-01 00:00:00

abstract：:Seedling establishment has long been believed to be rare on alpine tundra because of predicted life history trade-offs, the clonality of alpine species, and the harshness of the alpine climate. Contrary to the idea that seedlings are rare on alpine tundra, a 4-yr demographic study of seedlings at Niwot Ridge, Colorado...

journal_title：American journal of botany

authors： Forbis TA

更新日期：2003-08-01 00:00:00

abstract：PREMISE OF THE STUDY:Sex lability (i.e., gender diphasy) in plants is classically linked to the larger resource needs associated with the female sexual function (i.e., seed production) compared to the male function (i.e., pollen production). Sex lability in response to the environment is extensively documented in dioec...

journal_title：American journal of botany

authors： Varga S,Kytöviita MM

更新日期：2016-11-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Fuchsia (Onagraceae) anthers, pollen, and an ornithophilous Fuchsia-like flower from an earliest Miocene lacustrine diatomite deposit at Foulden Maar, southern New Zealand confirm a long record for Fuchsia in New Zealand and probably an equally long history for its distinctive honeyeat...

journal_title：American journal of botany

authors： Lee DE,Conran JG,Bannister JM,Kaulfuss U,Mildenhall DC

更新日期：2013-10-01 00:00:00

abstract：:Dispersal is an important life history component. Seed settling velocity may be a useful surrogate for the measurement of dispersal ability in wind-dispersed plants, particularly those whose seeds have plumose dispersal structures. I measured settling velocities on seeds of eight species of Asteraceae, including annua...

journal_title：American journal of botany

authors： Andersen MC

更新日期：1992-10-01 00:00:00

abstract：PREMISE:The ecological implications of hyperaccumulation have been investigated at the organismal level, but are poorly understood at the plant community level. Questions addressed here were: Does the presence of selenium (Se) hyperaccumulators affect Se distribution and concentration in their native soil, and do hyper...

journal_title：American journal of botany

authors： Reynolds RJB,Jones RR,Heiner J,Crane KM,Pilon-Smits EAH

更新日期：2020-07-01 00:00:00

abstract：PREMISE OF THE STUDY:Geographic differences in flower visitor assemblages might lead to among-population differences in the magnitude and pattern of floral integration. However, the role of current pollinator visitation in shaping the magnitude and pattern of floral trait correlations is still controversial. METHODS:W...

journal_title：American journal of botany

authors： Lázaro A,Santamaría L

更新日期：2016-02-01 00:00:00

abstract：PREMISE OF THE STUDY:The phenotype of an individual can be modified by the environment experienced by its predecessors, a phenomenon called transgenerational or maternal effects. These effects are studied mostly across sexual generations and are thought to be mediated also by epigenetic variation. However, we do not kn...

journal_title：American journal of botany

authors： González AP,Chrtek J,Dobrev PI,Dumalasová V,Fehrer J,Mráz P,Latzel V

更新日期：2016-09-01 00:00:00

abstract：:This study shows that structural data, when carefully examined, can provide valuable characters for delimiting monophyletic groups and can complement DNA with observable features to recognize and circumscribe taxa. In the angiosperm order Apiales, traditional classification has relied heavily (often exclusively) on fr...

journal_title：American journal of botany

authors： Liu MR,Plunkett GM,Lowry PP 2nd,Wyk BE,Tilney PM

更新日期：2006-09-01 00:00:00

abstract：:Responses to photoperiod and temperature were compared for hybrids between Asiatic plants in the indigenous strumarium morphological complex and plants in five American complexes: oviforme, italicum, chinense, cavanillesii, and pennsylvancium. The F1 hybrids between Hong Kong plants and various American plants showed ...

journal_title：American journal of botany

authors： McMillan C

更新日期：1975-01-01 00:00:00

abstract：PREMISE OF THE STUDY:Microsatellite loci were developed in the endangered Pericopsis elata using a combination of low-cost procedures. METHODS AND RESULTS:Microsatellite isolation was performed simultaneously on three distinct species through a newly available procedure that associates multiplex microsatellite enrichm...

journal_title：American journal of botany

authors： Micheneau C,Dauby G,Bourland N,Doucet JL,Hardy OJ

更新日期：2011-10-01 00:00:00

abstract：:The American chestnut (Castanea dentata; Fagaceae) was a dominant canopy tree in the Appalachian Mountains of North America. Since the introduction of the chestnut blight fungus (Cryphonectria parasitica; Valsaceae) in America, the American chestnut has been reduced to a predominantly clonal, understory species. Our o...

journal_title：American journal of botany

authors： Stilwell KL,Wilbur HM,Werth CR,Taylor DR

更新日期：2003-02-01 00:00:00

abstract：PREMISE OF THE STUDY:The ability of insect visitors to learn to manipulate complex flowers has important consequences for foraging efficiency and plant fitness. We investigated learning by two butterfly species, Danaus erippus and Heliconius erato, as they foraged on the complex flowers of Asclepias curassavica, as wel...

journal_title：American journal of botany

authors： Ramos BCM,Rodríguez-Gironés MA,Rodrigues D

更新日期：2017-08-01 00:00:00

abstract：:Field surveys of cynipid gall-inducer occurrences on Quercus species were conducted in Florida, North Carolina, and Pennsylvania, USA. All cynipids demonstrated strong host species and organ fidelity. One result of this specialization is effective niche partitioning among cynipids. The host-association patterns of the...

journal_title：American journal of botany

authors： Abrahamson W,Melika G,Scrafford R,Csoka G

更新日期：1998-08-01 00:00:00

abstract：:Senna (Leguminosae) is a large, widespread genus that includes species with enantiostylous, asymmetric flowers and species with extrafloral nectaries. Clarification of phylogenetic relationships within Senna based on parsimony analyses of three chloroplast regions (rpS16, rpL16, and matK) provides new insights on the ...

journal_title：American journal of botany

authors： Marazzi B,Endress PK,Queiroz LP,Conti E

更新日期：2006-02-01 00:00:00

abstract：PREMISE:Spiny pollen has evolved independently in multiple entomophilous lineages. Sexual selection may act on exine traits that facilitate male mating success by influencing the transfer of pollen from the anther to the body of the pollinator, while natural selection acts to increase pollen survival. We postulated tha...

journal_title：American journal of botany

authors： Lynn A,Piotter E,Harrison E,Galen C

更新日期：2020-02-01 00:00:00

abstract：PREMISE OF THE STUDY:Species formation is an intuitive endpoint of reproductive isolation, but circumscribing taxa that arise during speciation can be difficult because of gene flow, morphological continuity, hybridization or polyploidization, and low sequence variation among newly diverged lineages. Nonetheless, speci...

journal_title：American journal of botany

authors： Stoughton TR,Kriebel R,Jolles DD,O'Quinn RL

更新日期：2018-03-01 00:00:00

abstract：:Seedling establishment is central to population maintenance for nonclonal plant species. Plants with low recruitment rates are expected to have high survival rates, and life history theory indicates there should be a single curve for the trade-off between recruitment and mortality that applies to most or all plant spe...

journal_title：American journal of botany

authors： Forbis TA,Doak DF

更新日期：2004-07-01 00:00:00

abstract：:Species of Collinsia and Tonella, the two sister genera of self-compatible annuals that constitute tribe Collinsieae, show extensive variation in floral size and morphology and in patterns of stamen and style elongation during the life of the flower (anthesis). We used a nuclear ribosomal ITS phylogeny, independent co...

journal_title：American journal of botany

authors： Armbruster WS,Mulder CP,Baldwin BG,Kalisz S,Wessa B,Nute H

更新日期：2002-01-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Diversification of floral traits in angiosperms is often attributed to have been driven by adaptations to pollinators. Nevertheless, phylogenetic studies on the relationships among evolutionary changes in floral traits and pollination systems are still limited. We examined the relation...

journal_title：American journal of botany

authors： Sakai S,Kawakita A,Ooi K,Inoue T

更新日期：2013-03-01 00:00:00

abstract：:Sequence data from the intron and spacer of the trnL-F chloroplast region elucidate the phylogenetic relationships of the tribe Diseae (Orchidoideae: Orchidaceae). Within Diseae, 41 species of Disa, two of Brownleea, three of Satyrium, and two of Corycium were included, with five species of Habenaria sensu lato (Orchi...

journal_title：American journal of botany

authors： Bellstedt DU,Linder HP,Harley EH

更新日期：2001-11-01 00:00:00

abstract：PREMISE OF THE STUDY:Microsatellites were developed for the native, perennial herbs Houstonia longifolia and H. purpurea to establish rates and patterns of hybridization among these and other closely related lineages within the genus. METHODS AND RESULTS:Seven primer sets were developed and tested using populations ac...

journal_title：American journal of botany

authors： Glennon KL,Church SA

更新日期：2011-02-01 00:00:00

abstract：:The pitchers of the tropical carnivorous plant Nepenthes alata are highly specialized organs for the attraction and capture of insects and absorption of nutrients from them. This study examined the structure and development of these pitchers, with particular focus on the nectaries and digestive glands. Immature pitche...

journal_title：American journal of botany

authors： Owen TP Jr,Lennon KA

更新日期：1999-10-01 00:00:00

abstract：:Recent molecular phylogenetic studies of Solanaceae have identified many well-supported clades within the family and have permitted the creation of a phylogenetic system of classification. Here we estimate the phylogeny for Iochrominae, a clade of Physaleae sensu Olmstead et al. (1999), which contains 34 Andean specie...

journal_title：American journal of botany

authors： Smith SD,Baum DA

更新日期：2006-08-01 00:00:00

abstract：PREMISE OF THE STUDY:Recurrent formation of polyploid taxa is a common observation in many plant groups. Haploid, cytoplasmic genomes like the plastid genome can be used to overcome the problem of homeologous genes and recombination in polyploid taxa. Fragaria (Rosaceae) contains several octo- and decaploid species. We...

journal_title：American journal of botany

authors： Dillenberger MS,Wei N,Tennessen JA,Ashman TL,Liston A

更新日期：2018-05-01 00:00:00