Patterns of multiple paternity in fruits of Mimulus ringens (Phrymaceae).

abstract：:Expansion of Typha domingensis into areas previously dominated by Cladium jamaicense in the Florida Everglades has been linked to anthropogenic phosphorus (P) enrichment and increased hydroperiod. The principal stress factor for plants in flooded soils is biochemical reduction, the intensity of which is measured as re...

journal_title：American journal of botany

authors： Lissner J,Mendelssohn IA,Lorenzen B,Brix H,McKee KL,Miao S

更新日期：2003-05-01 00:00:00

abstract：:In monocarpic plants, reproduction is closely associated with senescence, which is itself often correlated to specific environmental signals. Floerkea proserpinacoides (Limnanthaceae) is a spring ephemeral annual of the deciduous forests of eastern North America. The phenology of its growth and reproduction is conside...

journal_title：American journal of botany

authors： Mokhtar IB,Houle G

更新日期：2005-03-01 00:00:00

abstract：:Bumble bee pollinated Chamaecrista fasciculata provides pollen as the sole reward to its pollinators. Male sterility, expressed as an absence or nearly complete absence of pollen production, occurs in low frequency in populations of C. fasciculata. Here we describe experiments, using C. fasciculata, to examine frequen...

journal_title：American journal of botany

authors： Williams HL,Fenster CB

更新日期：1998-09-01 00:00:00

abstract：:Seed mass is considered to be the least plastic component of reproductive yield. Yet, in invasive populations of garlic mustard, Alliaria petiolata, seed mass was highly variable (eightfold among populations, 2.5-7.5 fold within populations, two-threefold within individuals, and 1.4-1.8 fold within fruits). Variation ...

journal_title：American journal of botany

authors： Susko DJ,Lovett-Doust L

更新日期：2000-01-01 00:00:00

abstract：PREMISE OF THE STUDY:Areas lacking dominant plants, or gaps, can support high diversity and specialist species. Previous chronosequence research in Florida rosemary scrub showed indistinct gap area patterns with fire and the dependence of certain species on gaps. We hypothesized that fire and gap size would affect exti...

journal_title：American journal of botany

authors： Menges ES,Crate SJH,Quintana-Ascencio PF

更新日期：2017-12-01 00:00:00

abstract：PREMISE OF THE STUDY:The species boundaries of wild and cultivated potatoes are controversial, with most of the taxonomic problems in the cultivated potato clade. We here provide the first in-depth phylogenetic study of the cultivated potato clade to explore possible causes of these problems. METHODS:We examined 131 d...

journal_title：American journal of botany

authors： Spooner DM,Ruess H,Arbizu CI,Rodríguez F,Solís-Lemus C

更新日期：2018-01-01 00:00:00

abstract：:Restriction fragment length polymorphism (RFLP) analysis of chloroplast (cp) DNA is a powerful tool for the study of microevolutionary processes in land plants, yet has not previously been applied to seaweed populations. We used cpDNA-RFLP, detected on Southern blots using labeled total plastid DNA, to search for intr...

journal_title：American journal of botany

authors： Wattier RA,Davidson AL,Ward BA,Maggs CA

更新日期：2001-07-01 00:00:00

abstract：:The possible pathways of origin of two recently arisen introgressant forms of Senecio vulgaris (i.e., var. hibernicus and York radiate groundsel) were investigated in experimental crosses between tetraploid S. vulgaris var. vulgaris and the normally diploid S. squalidus. Comparison of the morphology of synthesized hyb...

journal_title：American journal of botany

authors： Lowe AJ,Abbott RJ

更新日期：2000-08-01 00:00:00

abstract：:Xylem of the orchids studied provided unusually favorable material to demonstrate how conductive tissue evolves in monocotyledons. In the end walls of tracheary elements of many Orchidaceae, remnants of pit membranes were observed with scanning electron microscopy and minimally destructive methods. The full range from...

journal_title：American journal of botany

authors： Carlquist S,Schneider EL

更新日期：2006-07-01 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：:We examined the effects of size and spatial isolation of fens on the isozyme variability of 17 populations of Swertia perennis. This long-lived perennial is a locally abundant fen specialist in Switzerland, where wetlands have been strongly fragmented. Isozyme variability was comparable to other outcrossing plants (A ...

journal_title：American journal of botany

authors： Lienert J,Fischer M,Schneller J,Diemer M

更新日期：2002-05-01 00:00:00

abstract：PREMISE OF THE STUDY:Autopolyploidy, or whole-genome duplication within a species, leads to closely related cytotypes in one geographic location. One hypothesized mechanism by which autopolyploids become established is climatic niche divergence from their diploid progenitor. Here we tested this hypothesis in diploid, t...

journal_title：American journal of botany

authors： Gaynor ML,Marchant DB,Soltis DE,Soltis PS

更新日期：2018-10-01 00:00:00

abstract：:Deciphering species relationships and hybrid origins in polyploid agamic species complexes is notoriously difficult. In this study of cheilanthoid ferns, we demonstrate increased resolving power for clarifying the origins of polyploid lineages by integrating evidence from a diverse selection of biosystematic methods. ...

journal_title：American journal of botany

authors： Grusz AL,Windham MD,Pryer KM

更新日期：2009-09-01 00:00:00

abstract：PREMISE OF THE STUDY:Pollen dispersal is a key process that influences ecological and evolutionary dynamics of plant populations by facilitating sexual reproduction and gene flow. Habitat loss and fragmentation have the potential to reduce pollen dispersal within and among habitat patches. We assessed aquatic pollen di...

journal_title：American journal of botany

authors： Lloyd MW,Tumas HR,Neel MC

更新日期：2018-02-01 00:00:00

abstract：PREMISE OF THE STUDY:Most pollen walls are interrupted by apertures, thin areas providing access to stigmatic fluids and exit points for pollen tubes. Unexpectedly, pollen tubes of Arabidopsis thaliana are not obligated to pass through apertures and can instead take the shortest route into the stigma, passing directly ...

journal_title：American journal of botany

authors： Edlund AF,Zheng Q,Lowe N,Kuseryk S,Ainsworth KL,Lyles RH,Sibener SJ,Preuss D

更新日期：2016-06-01 00:00:00

abstract：:• Premise of the study: Tropical forests are the most species-rich terrestrial communities on Earth, and understory trees and shrubs comprise a large fraction of their plant species diversity, especially at high rainfalls. The mechanisms responsible for generating such high levels of diversity remain unknown. One hypo...

journal_title：American journal of botany

authors： Theim TJ,Shirk RY,Givnish TJ

更新日期：2014-07-01 00:00:00

abstract：:We investigated the hypothesis that dandelion clones (Taraxacum officinale Weber, sensu lato; Asteraceae) differ in their floral stage timing characteristics under a constant set of environmental conditions. To test this hypothesis, plants representing nine different dandelion clones (identified by DNA fingerprinting)...

journal_title：American journal of botany

authors： Collier MH,Rogstad SH

更新日期：2004-11-01 00:00:00

abstract：:Ontogenetic trends in the wood structure of Nepalese Rhododendron were studied in 15 specimens of two tree and four subtree species. Average growth ring width was constant from pith to bark in spite of occurrences of extremely narrow, false, or discontinuous rings. Vessel density, vessel area, vessel element length, a...

journal_title：American journal of botany

authors： Noshiro S,Suzuki M

更新日期：2001-04-01 00:00:00

abstract：PREMISE OF THE STUDY:The genus Hoya (Apocynaceae; Asclepiadoideae) is characterized by a set of complex floral characters unique among the asclepiads, but their role in pollination is poorly understood. Here, we report a new mechanism of asclepiad pollination in the wax plant Hoya carnosa: the pollinaria are transferre...

journal_title：American journal of botany

authors： Mochizuki K,Furukawa S,Kawakita A

更新日期：2017-06-01 00:00:00

abstract：:Sphenobaiera huangii (Sze) Hsü is typical Early Mesozoic fossil foliage of Ginkgoales in China. It has been recorded from the Upper Triassic to the Lower Jurassic. The cuticular anatomy is investigated based on material from the type locality, Lower Jurassic Hsiangchi Formation, Zigui County, Hubei Province. The speci...

journal_title：American journal of botany

authors： Wang Y,Guignard G,Thévenard F,Dilcher D,Barale G,Mosbrugger V,Yang X,Mei S

更新日期：2005-04-01 00:00:00

abstract：:Investigations of the Middle Eocene Princeton Chert reveal evidence for the connection of lauraceous flowers to fruits through a developmental series. Youngest fruits are found with attached floral remnants. Later stages show receptacle enlargement, fruit wall thickening, and the development of abundant sclereid clust...

journal_title：American journal of botany

authors： Little SA,Stockey RA,Penner B

更新日期：2009-03-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Fungal plant pathogens exert much of their effect on plant cells through alterations in the host cell walls. However, obtaining biochemical proof for this change is difficult because of the relatively small number of cells that are affected by the pathogen relative to the bulk of host ...

journal_title：American journal of botany

authors： Bowling AJ,Vaughn KC,Hoagland RE,Stetina K,Boyette CD

更新日期：2010-12-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Verbenaceae consist of trees, shrubs, lianas, and herbs distributed primarily in Latin America, where they occur in a wide array of ecosystems. A second center of diversity exists in Africa. Competing morphology-based classifications that rely on different traits conflict in significan...

journal_title：American journal of botany

authors： Marx HE,O'Leary N,Yuan YW,Lu-Irving P,Tank DC,Múlgura ME,Olmstead RG

更新日期：2010-10-01 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：PREMISE:Within closed-canopy forests, vertical gradients of light and atmospheric CO2 drive variations in leaf carbon isotope ratios, leaf mass per area (LMA), and the micromorphology of leaf epidermal cells. Variations in traits observed in preserved or fossilized leaves could enable inferences of past forest canopy c...

journal_title：American journal of botany

authors： Cheesman AW,Duff H,Hill K,Cernusak LA,McInerney FA

更新日期：2020-08-01 00:00:00

abstract：:The genus Caltha (Ranunculaceae) consists of 10 species of low-growing, perennial herbs distributed throughout the moist temperate and cold regions of both the Northern and Southern Hemispheres. Traditionally, the species have been divided into two sections: section Psychrophila in the Southern Hemisphere with diploph...

journal_title：American journal of botany

authors： Schuettpelz E,Hoot SB

更新日期：2004-02-01 00:00:00

abstract：PREMISE OF THE STUDY:Male-biased herbivory in dioecious species is expected as a consequence of selection for increased resistance (reduced attack) in the sex with higher reproductive costs-females. Empirical support of this prediction is taxonomically restricted and fraught with exceptions. Phenological changes in res...

journal_title：American journal of botany

authors： Buckley NE,Avila-Sakar G

更新日期：2013-02-01 00:00:00

abstract：:This study examined variation in two components of acorn production. Percentage of bearing ramets (stems) and number of acorns per bearing ramet were examined in five clonal oaks in three xeric habitats of south-central peninsular Florida in relation to ramet size within and between species and vegetative associations...

journal_title：American journal of botany

authors： Abrahamson WG,Layne JN

更新日期：2002-01-01 00:00:00

abstract：:Contact forces are important in maintaining the twining habit of viny stems. A stem twining around a supporting pole puts itself into tension and uses a helical geometry to generate normal loads that are large relative to stem mass per unit length (Silk and Hubbard, Journal of Biomechanics 24(7):599-606, 1991). An ele...

journal_title：American journal of botany

authors： Matista A,Silk W

更新日期：1997-08-01 00:00:00

abstract：:The timing, geographical locations, causes, and consequences of crop domestication have long been major concerns of archaeologists, and agricultural origins and dispersals are currently more relevant than ever to scientists seeking solutions to elusive problems involving food insecurity and global health disparities. ...

journal_title：American journal of botany

authors： Langlie BS,Mueller NG,Spengler RN,Fritz GJ

更新日期：2014-10-01 00:00:00