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  • Geographic variation in climate as a proxy for climate change: Forecasting evolutionary trajectories from species differentiation and genetic correlations.

    abstract:PREMISE OF THE STUDY:Climate change models for California predict a warmer, drier future, potentially resulting in shorter growing seasons. If phenotypic differences between closely related species currently distributed across a moisture and temperature gradient represent adaptations to their abiotic environment, then ...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500108

    authors: Schneider HE,Mazer SJ

    更新日期:2016-01-01 00:00:00

  • Solidago altissima differs with respect to ploidy frequency and clinal variation across the prairie-forest biome border in Minnesota.

    abstract:PREMISE OF THE STUDY:Although our awareness of ploidy diversity has expanded with the application of flow cytometry, we still know little about the extent to which cytotypes within mixed-ploidy populations are genetically differentiated across environmental gradients. METHODS:To address this issue, we reared 14 popula...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500146

    authors: Etterson JR,Toczydlowski RH,Winkler KJ,Kirschbaum JA,McAulay TS

    更新日期:2016-01-01 00:00:00

  • The beta-diversity of species interactions: Untangling the drivers of geographic variation in plant-pollinator diversity and function across scales.

    abstract:PREMISE OF THE STUDY:Geographic patterns of biodiversity have long inspired interest in processes that shape the assembly, diversity, and dynamics of communities at different spatial scales. To study mechanisms of community assembly, ecologists often compare spatial variation in community composition (beta-diversity) a...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500079

    authors: Burkle LA,Myers JA,Belote RT

    更新日期:2016-01-01 00:00:00

  • Evolutionary insights from studies of geographic variation: Contemporary variation and looking to the future.

    abstract::In an age of rapid global change, it is imperative that we continue to improve our understanding of factors that govern genetic differentiation in plants to inform biologically reasonable predictions for the future and enlighten conservation and restoration practices. In this special issue, we have assembled a set of ...

    journal_title:American journal of botany

    pub_type:

    doi:10.3732/ajb.1500515

    authors: Etterson JR,Schneider HE,Gorden NL,Weber JJ

    更新日期:2016-01-01 00:00:00

  • The influence of herbivory on pre- and postzygotic stages of reproduction following open, self, and outcross pollination.

    abstract:PREMISE OF THE STUDY:Herbivory affects pollination success and reproductive output in plants. However, the different stages in the process from pollination to seed maturation have hardly been investigated within the context of herbivory. Herbivory might affect these stages via its effect on geitonogamous pollination an...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500291

    authors: Ghyselen C,Bonte D,Brys R

    更新日期:2015-12-01 00:00:00

  • Low flower-size variation in bilaterally symmetrical flowers: Support for the pollination precision hypothesis.

    abstract:PREMISE OF THE STUDY:The evolutionary shift from radial to bilateral symmetry in flowers is generally associated with the evolution of low flower-size variation. This phenomenon supports the hypothesis that the lower size variation in bilateral flowers can be attributed to low pollinator diversity. In this study, we pr...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500371

    authors: Nikkeshi A,Kurimoto D,Ushimaru A

    更新日期:2015-12-01 00:00:00

  • Paraphyly changes understanding of timing and tempo of diversification in subtribe Hakeinae (Proteaceae), a giant Australian plant radiation.

    abstract:PREMISE OF THE STUDY:Subtribe Hakeinae (526 spp.) represents a large Australian plant radiation central to our understanding of that flora's evolution and ecology. It contains Grevillea-the third largest plant genus in Australia and a group inferred to have among the highest diversification rates in the angiosperms. Ho...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500195

    authors: Mast AR,Olde PM,Makinson RO,Jones E,Kubes A,Miller ET,Weston PH

    更新日期:2015-10-01 00:00:00

  • Pollen structure and development in Nymphaeales: insights into character evolution in an ancient angiosperm lineage.

    abstract:PREMISE OF THE STUDY:A knowledge of pollen characters in early-diverging angiosperm lineages is essential for understanding pollen evolution and the role of pollen in angiosperm diversification. In this paper, we report and synthesize data on mature pollen and pollen ontogeny from all genera of Nymphaeales within a com...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500249

    authors: Taylor ML,Cooper RL,Schneider EL,Osborn JM

    更新日期:2015-10-01 00:00:00

  • Barrancaceae: A new green algal lineage with structural and behavioral adaptations to a fluctuating environment.

    abstract:PREMISE OF THE STUDY:To enhance our knowledge of the diversity of microalgae, a phycological survey of the Canary Islands (Spain) was undertaken. Here we report the discovery of a (semi)terrestrial green filamentous alga isolated from a steep volcanic canyon on La Palma. This alga is continually exposed to changing wea...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500199

    authors: Caisová L,Reyes CP,Álamo VC,Quintana AM,Surek B,Melkonian M

    更新日期:2015-09-01 00:00:00

  • Long-term shifts in the phenology of rare and endemic Rocky Mountain plants.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Mountainous regions support high plant productivity, diversity, and endemism, yet are highly vulnerable to climate change. Historical records and model predictions show increasing temperatures across high elevation regions including the Southern Rocky Mountains, which can have a stron...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500156

    authors: Munson SM,Sher AA

    更新日期:2015-08-01 00:00:00

  • Cytotype distribution patterns, ecological differentiation, and genetic structure in a diploid-tetraploid contact zone of Cardamine amara.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Contact zones between diploids and their autopolyploid descendants represent a unique evolutionary venue for studying polyploid establishment, cytotype coexistence, and interactions. Here, we examine cytotype coexistence in a diploid-tetraploid contact zone of a perennial herb, Cardam...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500052

    authors: Zozomová-Lihová J,Malánová-Krásná I,Vít P,Urfus T,Senko D,Svitok M,Kempa M,Marhold K

    更新日期:2015-08-01 00:00:00

  • Tempo and mode of flower color evolution.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Flower color is one of the best-studied floral traits in terms of its genetic basis and ecological significance, yet few studies have examined the processes that shape its evolution across deep timescales. Advances in comparative methods along with larger phylogenies for floral radiat...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500163

    authors: Smith SD,Goldberg EE

    更新日期:2015-07-01 00:00:00

  • Morphology delimits more species than molecular genetic clusters of invasive Pilosella.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Accurate assessments of biodiversity are paramount for understanding ecosystem processes and adaptation to change. Invasive species often contribute substantially to local biodiversity; correctly identifying and distinguishing invaders is thus necessary to assess their potential impac...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400466

    authors: Moffat CE,Ensing DJ,Gaskin JF,De Clerck-Floate RA,Pither J

    更新日期:2015-07-01 00:00:00

  • Foliar secretory structures in Crotoneae (Euphorbiaceae): Diversity, anatomy, and evolutionary significance.

    abstract:PREMISE OF THE STUDY:Phylogenetic and morphological studies have helped clarify the systematics of large and complex groups such as the tribe Crotoneae (Euphorbiaceae). However, very little is known about the diversity, structure, and function of anatomical features in this tribe. Crotoneae comprises the species-rich p...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500017

    authors: Vitarelli NC,Riina R,Caruzo MB,Cordeiro I,Fuertes-Aguilar J,Meira RM

    更新日期:2015-06-01 00:00:00

  • Seasonal changes in physiological performance in wild Clarkia xantiana populations: Implications for the evolution of a compressed life cycle and self-fertilization.

    abstract:PREMISE OF THE STUDY:One explanation for the evolution of selfing, the drought escape hypothesis, proposes that self-fertilization may evolve under conditions of intensifying seasonal drought as part of a suite of traits that enable plants to accelerate the completion of their life cycle, thereby escaping late-season d...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400557

    authors: Dudley LS,Hove AA,Emms SK,Verhoeven AS,Mazer SJ

    更新日期:2015-06-01 00:00:00

  • Indirect effects of herbivory on plant-pollinator interactions in invasive Lythrum salicaria.

    abstract:PREMISE OF THE STUDY:Herbivory can affect a plant's fitness in a variety of ways, including modifying the biotic interactions of the plant. In particular, when herbivory influences floral display, we hypothesize that pollinator visitation will be altered accordingly. Here we studied the indirect effects of feeding by t...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1500043

    authors: Russell-Mercier JL,Sargent RD

    更新日期:2015-05-01 00:00:00

  • Phylogenetic relationships in Asarum: Effect of data partitioning and a revised classification.

    abstract:PREMISE OF THE STUDY:Generic boundaries and infrageneric relationships among the charismatic temperate magnoliid Asarum sensu lato (Aristolochiaceae) have long been uncertain. Previous molecular phylogenetic analyses used either plastid or nuclear loci alone and varied greatly in their taxonomic implications for the ge...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400316

    authors: Sinn BT,Kelly LM,Freudenstein JV

    更新日期:2015-05-01 00:00:00

  • Assessing the impact of phylogenetic incongruence on taxonomy, floral evolution, biogeographical history, and phylogenetic diversity.

    abstract:PREMISE OF THE STUDY:Phylogenetic incongruence between "gene trees" and "species trees" has been widely acknowledged in phylogenetic research. Conflicts may emerge from several processes including paralogy, hybridization, and incomplete lineage sorting. Although phylogenetic incongruence appears common, its impact on m...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400527

    authors: Zhang Q,Feild TS,Antonelli A

    更新日期:2015-04-01 00:00:00

  • Evolutionary divergence of leaf width and its correlates.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:The question why leaf dimensions vary so much between species has long puzzled ecologists. Presumably, variation arises from selective forces acting on leaf function but which selective forces and which leaf functions? This investigation assesses the consistency of divergence in plant...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400379

    authors: Tozer WC,Rice B,Westoby M

    更新日期:2015-03-01 00:00:00

  • The ecology, evolution, and biogeography of dioecy in the genus Solanum: with paradigms from the strong dioecy in Solanum polygamum, to the unsuspected and cryptic dioecy in Solanum conocarpum.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Island plants are over-exploited and "under-explored." Understanding the reproductive biology of plants, especially rare species, is fundamental to clarifying their evolution, estimating potential for change, and for creating effective conservation plans. Clarification of sexual syste...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400486

    authors: Anderson GJ,Anderson MK,Patel N

    更新日期:2015-03-01 00:00:00

  • A Late Cretaceous Piper (Piperaceae) from Colombia and diversification patterns for the genus.

    abstract:PREMISE OF THE STUDY:Documented fossil floras in the neotropics are sparse, yet their records provide evidence on the spatial and temporal occurrence of taxa, allowing for testing of biogeographical and diversification scenarios on individual lineages. A new fossil Piper from the Late Cretaceous of Colombia is describe...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400427

    authors: Martínez C,Carvalho MR,Madriñán S,Jaramillo CA

    更新日期:2015-02-01 00:00:00

  • Plastic responses of native plant root systems to the presence of an invasive annual grass.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:The ability to respond to environmental change via phenotypic plasticity may be important for plants experiencing disturbances such as climate change and plant invasion. Responding to belowground competition through root plasticity may allow native plants to persist in highly invaded ...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400234

    authors: Phillips AJ,Leger EA

    更新日期:2015-01-01 00:00:00

  • Ever since Klekowski: testing a set of radical hypotheses revives the genetics of ferns and lycophytes.

    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

    pub_type: 杂志文章,评审

    doi:10.3732/ajb.1400317

    authors: Haufler CH

    更新日期:2014-12-01 00:00:00

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

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Two ovulate conifer cones, one of which is attached terminally to a short leafy shoot, reveal the presence of a new species of Hughmillerites in the Early Cretaceous Apple Bay flora of Vancouver Island, British Columbia, Canada. This ancient conifer expands the diversity of Cupressace...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400369

    authors: Atkinson BA,Rothwell GW,Stockey RA

    更新日期:2014-12-01 00:00:00

  • Complete life cycle of the lichen fungus Calopadia puiggarii (Pilocarpaceae, Ascomycetes) documented in situ: propagule dispersal, establishment of symbiosis, thallus development, and formation of sexual and asexual reproductive structures.

    abstract:PREMISE OF THE STUDY:The life histories of lichen fungi are not well known and cannot be readily studied in laboratory culture. This work documents in situ the complete life cycle of the widespread crustose lichen Calopadia puiggarii, which reproduces sexually and asexually on the surfaces of leaves. METHODS:Plastic c...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400272

    authors: Sanders WB

    更新日期:2014-11-01 00:00:00

  • Remnants of populations provide effective source material for reintroduction of an endangered Hawaiian plant, Schiedea kaalae (Caryophyllaceae).

    abstract:PREMISE OF THE STUDY:Reintroductions may be essential to prevent extinction of many critically endangered species. Ideally, reintroduction efforts rely on adjacent source populations, but limited source material may necessitate crossing individuals from different and possibly distant populations. To determine the conse...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400271

    authors: Weisenberger LA,Weller SG,Sakai AK

    更新日期:2014-11-01 00:00:00

  • Agricultural origins from the ground up: archaeological approaches to plant domestication.

    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

    pub_type: 杂志文章

    doi:10.3732/ajb.1400145

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

    更新日期:2014-10-01 00:00:00

  • Genomics: a potential panacea for the perennial problem.

    abstract::Perennial crops represent important fresh and processed food sources worldwide, but advancements in breeding perennials are often impeded due to their very nature. The perennial crops we rely on most for food take several years to reach production maturity and require large spaces to grow, which make breeding new cult...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400143

    authors: McClure KA,Sawler J,Gardner KM,Money D,Myles S

    更新日期:2014-10-01 00:00:00

  • Population genetics and origin of the native North American agricultural weed waterhemp (Amaranthus tuberculatus; Amaranthaceae).

    abstract:UNLABELLED:• PREMISE OF THE STUDY:The evolution of invasiveness has been extensively studied in natural ecosystems; however, far less is known about the evolution of agricultural invasiveness, despite the major economic impact of weeds on crop productivity. Examining the population structure of recently arisen weeds c...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400064

    authors: Waselkov KE,Olsen KM

    更新日期:2014-10-01 00:00:00

  • Phloem development: current knowledge and future perspectives.

    abstract::Phloem, as a major tissue mediating long-distance communication, has been an object of extensive research ever since its structure was first reported in 1837. Functional phloem consists of sieve elements (SEs) and companion cells (CCs). While SEs are enucleated conducting cells in the phloem, CCs are cells with intact...

    journal_title:American journal of botany

    pub_type: 杂志文章,评审

    doi:10.3732/ajb.1400197

    authors: Heo JO,Roszak P,Furuta KM,Helariutta Y

    更新日期:2014-09-01 00:00:00

  • The African baobab (Adansonia digitata, Malvaceae): genetic resources in neglected populations of the Nuba Mountains, Sudan.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:Adansonia digitata L. is one of the most important indigenous fruit trees of mainland Africa. Despite its significance for subsistence and income generation of local communities, little is known about the genetic and morphological variability of East African populations of A. digitata...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400198

    authors: Wiehle M,Prinz K,Kehlenbeck K,Goenster S,Mohamed SA,Finkeldey R,Buerkert A,Gebauer J

    更新日期:2014-09-01 00:00:00

  • Attracting mutualists and antagonists: plant trait variation explains the distribution of specialist floral herbivores and pollinators on crops and wild gourds.

    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

    pub_type: 杂志文章

    doi:10.3732/ajb.1400171

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

    更新日期:2014-08-01 00:00:00

  • The structure and development of incompletely closed carpels in an apocarpous species, Sagittaria trifolia (Alismataceae).

    abstract::• Premise of the study: Carpel closure is commonly considered as a key innovation in angiosperms; however, some families continue to exhibit a variety of forms of incomplete carpel closure. The carpel of Sagittaria species contains an unusual structure. In this study, we confirm the closure type of the carpel of Sagit...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400172

    authors: Huang LJ,Wang XW,Wang XF

    更新日期:2014-07-01 00:00:00

  • Spatial genetic structure in four understory Psychotria species (Rubiaceae) and implications for tropical forest diversity.

    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

    pub_type: 杂志文章

    doi:10.3732/ajb.1300460

    authors: Theim TJ,Shirk RY,Givnish TJ

    更新日期:2014-07-01 00:00:00

  • Habitat fragmentation threatens wild populations of Carica papaya (Caricaceae) in a lowland rainforest.

    abstract::• Premise of the study: Wild populations of domesticated species constitute a genetic reservoir and are fundamental to the evolutionary potential of species. Wild papaya (Carica papaya) is a rare, short-lived, gap-colonizing, dioecious tree that persists in the forest by continuous dispersal. Theoretically, these life...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400051

    authors: Chávez-Pesqueira M,Suárez-Montes P,Castillo G,Núñez-Farfán J

    更新日期:2014-07-01 00:00:00

  • Bending properties of a macroalga: Adaptation of Peirce's cantilever test for in situ measurements of Laminaria digitata (Laminariaceae).

    abstract::• Premise of the study: The mechanical properties of a plant are key variables governing the interaction between the plant and its environment. Thus, measuring variables such as the flexural rigidity (bending) of a plant element is necessary to understand and predict the plant-flow interaction. However, plant elements...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400163

    authors: Henry PY

    更新日期:2014-06-01 00:00:00

  • An experimental approach to explain the southern Andes elevational treeline.

    abstract:UNLABELLED:• PREMISE OF THE STUDY:The growth limitation hypothesis (GLH) is the most accepted mechanistic explanation for treeline formation, although it is still uncertain whether it applies across taxa. The successful establishment of Pinus contorta--an exotic conifer species in the southern hemisphere--above the No...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1400166

    authors: Fajardo A,Piper FI

    更新日期:2014-05-01 00:00:00

  • Is gene flow the most important evolutionary force in plants?

    abstract::Although theory has demonstrated rather low levels of gene flow are sufficient to counteract opposing mutation, drift, and selection, widespread recognition of the evolutionary importance of gene flow has come slowly. The perceived role of gene flow as an evolutionary force has vacillated over the last century. In the...

    journal_title:American journal of botany

    pub_type: 杂志文章,评审

    doi:10.3732/ajb.1400024

    authors: Ellstrand NC

    更新日期:2014-05-01 00:00:00

  • A comparison of 16 DNA regions for use as phylogenetic markers in the pleurocarpous moss genus Plagiothecium (Hypnales).

    abstract:PREMISE OF THE STUDY:Within the Hypnales-the most derived and species-rich order of pleurocarpous mosses - phylogenies at or below the family level often show poor resolution. In preparation for a phylogeny of the genus Plagiothecium, we wished to identify the DNA markers best suited for evolutionary reconstruction in ...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1300269

    authors: Wynns JT,Lange CB

    更新日期:2014-04-01 00:00:00

  • The nature of serpentine endemism.

    abstract::Serpentine soils are a model system for the study of plant adaptation, speciation, and species interactions. Serpentine soil is an edaphically stressful, low productivity soil type that hosts stunted vegetation and a spectacular level of plant endemism. One of the first papers on serpentine plant endemism was by Arthu...

    journal_title:American journal of botany

    pub_type: 杂志文章

    doi:10.3732/ajb.1300349

    authors: Anacker BL

    更新日期:2014-02-01 00:00:00

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