Hughmillerites vancouverensis sp. nov. and the Cretaceous diversification of Cupressaceae.

abstract：:Gaura (Onagraceae: Onagreae) is a small North American genus of 21 species consisting mostly of night-blooming, moth-pollinated annuals and perennials. The current infrageneric classification based on differences in habit, floral symmetry, and fruit morphology recognizes eight sections within the genus. We examine the...

journal_title：American journal of botany

authors： Hoggard GD,Kores PJ,Molvray M,Hoggard RK

更新日期：2004-01-01 00:00:00

abstract：:Much of the ultraviolet-B radiation (UV-B) research on plants has concentrated on vegetative plant parts, and only a small fraction has dealt with the reproductive system. The present study analyzed pollen grains of 34 taxa germinated and grown under two levels of UV-B radiation (187 and 460 mW/m2) or no UV-B (control...

journal_title：American journal of botany

authors： Torabinejad J,Caldwell M,Flint S,Durham S

更新日期：1998-03-01 00:00:00

abstract：:The amplified fragment length polymorphism (AFLP) method was used to evaluate genetic diversity and to assess genetic relationships within the section Mentha in order to clarify the taxonomy of several interspecific mint hybrids with molecular markers. To this end, genetic diversity of 62 Mentha accessions from differ...

journal_title：American journal of botany

authors： Gobert V,Moja S,Colson M,Taberlet P

更新日期：2002-12-01 00:00:00

abstract：PREMISE OF THE STUDY:Plant communities may be influenced by toxic secondary metabolites or enhanced plant growth from plant-symbiont interactions. The C:N hypothesis predicts that carbon or nitrogen constrains plant secondary metabolite production, but it does not consider compounds produced by plant symbionts. Locowee...

journal_title：American journal of botany

authors： Delaney KJ,Klypina N,Maruthavanan J,Lange C,Sterling TM

更新日期：2011-12-01 00:00:00

abstract：PREMISE OF THE STUDY:A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to...

journal_title：American journal of botany

authors： Kriebel R,Drew BT,Drummond CP,González-Gallegos JG,Celep F,Mahdjoub MM,Rose JP,Xiang CL,Hu GX,Walker JB,Lemmon EM,Lemmon AR,Sytsma KJ

更新日期：2019-04-01 00:00:00

abstract：:Welwitschiaceae, a family in the Gnetales, is known today from only one extant species, Welwitschia mirabilis. This species is distributed in the Namibian desert, along the western coast of southern Africa, about 10 km inland from the coast. Very little is known about the fossil record of this family. Lower Cretaceous...

journal_title：American journal of botany

authors： Dilcher DL,Bernardes-De-Oliveira ME,Pons D,Lott TA

更新日期：2005-08-01 00:00:00

abstract：:Many plant species are characterized by a life cycle with a long-lived, subterranean phase that is completely dependent on mycorrhizal fungal symbionts for fixed carbon. This type of life cycle is both phylogenetically and ecologically widespread and is found in diverse vascular plant lineages from the tropics to suba...

journal_title：American journal of botany

authors： Winther JL,Friedman WE

更新日期：2007-07-01 00:00:00

abstract：:Pedilanthus coalcomanensis was described from specimens collected by George B. Hinton in 1941 but was not collected again until 1999, when we found it in a tropical deciduous forest near Tehuantepec, in Chinicuila, Michoacán, Mexico. After analyzing Hinton's original collection notes, we concluded that this is the typ...

journal_title：American journal of botany

authors： Lomelí-Sención JA,Sahagún-Godínez E

更新日期：2002-09-01 00:00:00

abstract：PREMISE OF THE STUDY:Eocene caldera-lake beds at Laguna del Hunco (LH, ca. 52.2 Ma) and Río Pichileufú (RP, ca. 47.7 Ma) in Argentine Patagonia provide copious information about the biological history of Gondwana. Several plant genera from these sites are known as fossils from southern Australia and New Zealand and sur...

journal_title：American journal of botany

authors： Wilf P

更新日期：2012-03-01 00:00:00

abstract：PREMISE OF THE STUDY:Seabirds often cause significant changes to soil properties, and seabird-dominated systems often host unique plant communities. This study experimentally (1) examined species-specific responses to seabird guano gradients, (2) considered the role that differential functional traits among species pla...

journal_title：American journal of botany

authors： Young HS,McCauley DJ,Dirzo R

更新日期：2011-02-01 00:00:00

abstract：PREMISE OF THE STUDY:During the interactions between a parasitic plant and its host, the parasite affects its host morphologically, anatomically, and physiologically, yet there has been little focus on the effect of hosts on the parasite. Here, the functional interactions between the hemiparasitic mistletoe Psittacanth...

journal_title：American journal of botany

authors： Cocoletzi E,Angeles G,Ceccantini G,Patrón A,Ornelas JF

更新日期：2016-06-01 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：PREMISE:Variation in seedling emergence timing is considered adaptive over the long term in wild populations, but early emergence can result in a fitness advantage. To explore the adaptive significance of seedling emergence timing, it should be studied under realistic conditions and in the context of other traits that ...

journal_title：American journal of botany

authors： Mercer KL,Alexander HM,Snow AA

更新日期：2011-06-01 00:00:00

abstract：PREMISE OF THE STUDY:Population genetic structuring over limited timescales is commonly viewed as a consequence of spatial constraints. Indirect approaches have recently revealed reproductive isolation resulting from flowering time (so-called isolation by time, IBT). Since phenological processes can be subject to selec...

journal_title：American journal of botany

authors： Daïnou K,Laurenty E,Mahy G,Hardy OJ,Brostaux Y,Tagg N,Doucet JL

更新日期：2012-09-01 00:00:00

abstract：:The biological nature of some symbioses is unclear because it is often not easy to discern whether the symbionts obtain any benefits from the association. Mastodia tessellata, a symbiosis between a leafy green alga and a fungus of uncertain phylogenetic position, is among the most investigated, controversial, and poor...

journal_title：American journal of botany

authors： Pérez-Ortega S,Ríos Ade L,Crespo A,Sancho LG

更新日期：2010-05-01 00:00:00

abstract：:Light propagation and distribution inside leaves have been recognized as important processes influencing photosynthesis. Monochromatic light absorption across the mesophyll was measured using chlorophyll fluorescence generated from illumination of the cut edge (epi-illumination), as well as the adaxial or abaxial surf...

journal_title：American journal of botany

authors： Johnson DM,Smith WK,Vogelmann TC,Brodersen CR

更新日期：2005-09-01 00:00:00

abstract：:Yucca glauca is a C(3) evergreen rosette species locally common in the C(4)-dominated grasslands of the central Great Plains. Most congeners of Y. glauca are found in deserts, and Y. glauca's morphological similarities to desert species (steeply angled leaves, evergreen habit) may be critical to its success in grassla...

journal_title：American journal of botany

authors： Maragni LA,Knapp AK,McAllister CA

更新日期：2000-02-01 00:00:00

abstract：:There have been three periods of significant discovery in the exploration of fern and lycophyte genetics. First, during the 1930s, Andersson-Kottö conducted crossing studies on ferns. The publication of Manton's magnum opus on fern chromosomes in 1950 stimulated the second. The third emerged from Klekowski's 1973 Amer...

journal_title：American journal of botany

authors： Haufler CH

更新日期：2014-12-01 00:00:00

abstract：UNLABELLED:• PREMISE OF THE STUDY:Floral traits play important roles in pollinator attraction and defense against floral herbivory. However, plants may experience trade-offs between conspicuousness to pollinators and herbivore attraction. Comparative studies provide an excellent framework to examine the role of multip...

journal_title：American journal of botany

authors： Theis N,Barber NA,Gillespie SD,Hazzard RV,Adler LS

更新日期：2014-08-01 00:00:00

abstract：:Molecular studies of apomictic plant species often detect more genotypic variation than predicted from their assumed reproductive mode. The two most commonly invoked mechanisms to explain these high levels of variation are recombination, via facultative sexuality, and mutation. The potential for sexual reproduction in...

journal_title：American journal of botany

authors： Houliston GJ,Chapman HM

更新日期：2004-01-01 00:00:00

abstract：:Interspecific hybridization is considered a possible mechanism of plant diversification. The Andes are a hotspot of biodiversity, but hybridization in Andean taxa has so far not been investigated intensively. The current study investigates crossability in Caiophora (Loasaceae subfam. Loasoideae) by experimental inters...

journal_title：American journal of botany

authors： Ackermann M,Achatz M,Weigend M

更新日期：2008-09-01 00:00:00

abstract：:Fitness of interspecific hybrids is sometimes high relative to their parents, despite the conventional belief that they are mostly unfit. F(1) hybrids between oilseed rape (Brassica napus) and weedy B. rapa can be significantly more fit than their weedy parents under some conditions; however, under other conditions th...

journal_title：American journal of botany

authors： Hauser TP,Damgaard C,Jørgensen RB

更新日期：2003-04-01 00:00:00

abstract：:Ontogenetic changes in architecture, carbohydrate reserves, and resource allocation can constrain the ability of plants to compensate for herbivore damage. To evaluate ontogenetic changes in compensation, saplings and reproductive individuals of the tropical tree Casearia nitida were subjected to three levels of defol...

journal_title：American journal of botany

authors： Boege K

更新日期：2005-10-01 00:00:00

abstract：PREMISE OF THE STUDY:Microsatellite primers were developed in the traditional Tibetan medicinal plant Halenia elliptica D. Don to investigate its genetic diversity and population genetic structure. METHODS AND RESULTS:Using the Fast Isolation by AFLP of Sequences Containing (FIASCO) repeats protocol, 24 primer sets we...

journal_title：American journal of botany

authors： Zhang ZR,Yang J,Sun Y,Gao TG,Li DZ,Xue CY

更新日期：2011-07-01 00:00:00

abstract：PREMISE:Woody plants with photosynthetic stems are common in the drylands of the world; however, we know little about the origin(s) and geographical distribution of photosynthetic stems. Therefore, we set to answer the following questions: (1) Is stem photosynthesis phylogenetically conserved? (2) Do green-stemmed and ...

journal_title：American journal of botany

authors： Ávila-Lovera E,Garcillán PP

更新日期：2020-12-06 00:00:00

abstract：:Darwin's research on botany and plant physiology was a landmark attempt to integrate plant movements into a biological perspective of behavior. Since antiquity, people have sought to explain plant movements via mechanical or physiological forces, and yet they also constructed analogies between plant and animal behavio...

journal_title：American journal of botany

authors： Whippo CW,Hangarter RP

更新日期：2009-12-01 00:00:00

abstract：:The fossil record of aquatic flowering plants broadens our understanding of their former diversity and origins from terrestrial ancestors. This paper describes a floating aquatic monocot from 71 whole plants and several isolated leaf fragments from Upper Cretaceous oxbow lake sediments in the Dinosaur Park Formation, ...

journal_title：American journal of botany

authors： Stockey RA,Rothwell GW,Johnson KR

更新日期：2007-04-01 00:00:00

abstract：PREMISE OF THE STUDY:Our goal was to infer the phylogenetic relationships and historical biogeography of the genus Dryopteris with a focus on taxa in sub-Saharan Africa and neighboring islands. In general, little is known about the relationships between African fern species and their congeners in other geographic regio...

journal_title：American journal of botany

authors： Sessa EB,Juslén A,Väre H,Chambers SM

更新日期：2017-03-01 00:00:00

abstract：:We studied 15 riparian and upland Sonoran desert species to evaluate how the limitation of xylem pressure (Ψ(x)) by cavitation corresponded with plant distribution along a moisture gradient. Riparian species were obligate riparian trees (Fraxinus velutina, Populus fremontii, and Salix gooddingii), native shrubs (Bacch...

journal_title：American journal of botany

authors： Pockman WT,Sperry JS

更新日期：2000-09-01 00:00:00

abstract：:To investigate the relationship between the altitudinal distribution of Quercus laceyi and Q. sideroxyla and their physiological responses to drought, we measured relative water content (RWC), water potentials (Ψ(predawn) and Ψ(midday)), photosynthesis (A(max)), stomatal conductance (g), chlorophyll fluorescence (F(v)...

journal_title：American journal of botany

authors： Poulos HM,Goodale UM,Berlyn GP

更新日期：2007-05-01 00:00:00