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

abstract：:Polyploid speciation is an ongoing, important source of angiosperm diversity. However, the barriers to polyploid speciation and mechanisms of establishment remain poorly understood for all but a few species. Several factors likely to have influenced tetraploid establishment, including barriers to triploid formation, c...

journal_title：American journal of botany

authors： Baack EJ

更新日期：2005-11-01 00:00:00

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

authors： Anderson GJ,Anderson MK,Patel N

更新日期：2015-03-01 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：:A conspicuous feature of Vochysiaceae flowers is their single fertile stamen. In some genera, the stamen is in front of a petal, whereas in others it is in front of a sepal. This difference has been attributed to two independent reductions, which implies the stamen is not homologous across the family. The observation ...

journal_title：American journal of botany

authors： Litt A,Stevenson DW

更新日期：2003-11-01 00:00:00

abstract：PREMISE OF THE STUDY:Functional trait plasticity in resource capture traits has been suggested as an underlying mechanism promoting invasive species establishment and spread. Earlier studies on this mechanism treat invasiveness as a discrete characteristic (i.e., invasive vs. noninvasive) and do not consider the potent...

journal_title：American journal of botany

authors： Murphy JE,Burns JH,Fougère-Danezan M,Drenovsky RE

更新日期：2016-12-01 00:00:00

abstract：:We present here the first molecular phylogeny of tribe Diseae (Orchidoideae: Orchidaceae). Nuclear ribosomal ITS1, 5.8S rDNA, and ITS2 sequences were compared for 30 Diseae, 20 Orchideae, and four Cranichideae and Diurideae outgroups. ITS - rDNA sequences exhibited a transition:transversion ratio of 1.3 and extensive ...

journal_title：American journal of botany

authors： Douzery EJ,Pridgeon AM,Kores P,Linder HP,Kurzweil H,Chase MW

更新日期：1999-06-01 00:00:00

abstract：:Herbivore damage is known to cause the premature loss of mature leaves. However, the effects of herbivory on abscission during the early stages of leaf development remain unexplored, even though herbivores frequently prefer unlignified, immature leaves. In a field experiment, we removed 50% of the tissue from leaves a...

journal_title：American journal of botany

authors： Blundell AG,Peart DR

更新日期：2000-11-01 00:00:00

abstract：:Chloroplast DNA (cpDNA) is maternally inherited in the majority, but not all, of angiosperm species. The mode of inheritance of cpDNA is a critical determinant of its molecular evolution and of its population genetic structure. Here, we present the results of investigations of the inheritance of cpDNA in Silene vulgar...

journal_title：American journal of botany

authors： McCauley DE,Sundby AK,Bailey MF,Welch ME

更新日期：2007-08-01 00:00:00

abstract：:Natural recruitment of oaks appears to be declining throughout the northern hemisphere. Summer drought poses a potentially important barrier to oak recruitment in southern California. To evaluate this barrier, we grew evergreen Quercus agrifolia and deciduous Q. lobata from seeds near parental trees. We measured water...

journal_title：American journal of botany

authors： Mahall BE,Tyler CM,Cole ES,Mata C

更新日期：2009-04-01 00:00:00

abstract：:Phylogenetic relationships were determined in the Araucariaceae, which are now found mainly in the Southern Hemisphere. This conifer family was well diversified and widely distributed in both hemispheres during the Mesozoic era. The sequence of 1322 bases of the rbcL gene of cpDNA was determined from 29 species of Ara...

journal_title：American journal of botany

authors： Setoguchi H,Asakawa Osawa T,Pintaud JC,Jaffré T,Veillon JM

更新日期：1998-11-01 00:00:00

abstract：:Seeds are useful in distinguishing among extant genera of Vitaceae and provide a good basis for interpretation of fossil remains in reconstructing the evolutionary and phytogeographic history of this putatively basal Rosid family. Seeds of Ampelocissus s.l. including Pterisanthes and Nothocissus are distinguished from...

journal_title：American journal of botany

authors： Chen I,Manchester SR

更新日期：2007-09-01 00:00:00

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

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

更新日期：2014-10-01 00:00:00

abstract：PREMISE OF THE STUDY:In angiosperm seeds, the developing embryo acquires nutrients via a suspensor that typically undergoes programmed cell death (PCD) at the early cotyledon stage. However, in Leguminosae (the third largest angiosperm family), the suspensors can disappear at the heart-shaped stage (i.e., prior to the ...

journal_title：American journal of botany

authors： Endo Y

更新日期：2012-08-01 00:00:00

abstract：:Atriplex prostrata Boucher, a facultative halophyte, exhibits significant reduction in height and biomass and in the width of the cortex and vascular tissue under saline conditions. Therefore, the goal of this investigation was to determine the effect of salinity on plant growth as well as on the patterns of lignifica...

journal_title：American journal of botany

authors： Wang L,Showalter A,Ungar I

更新日期：1997-09-01 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

abstract：:Bennettitales is an extinct group of seed plants with reproductive structures that are similar in some respects to both Gnetales and angiosperms, but systematic relationships among the three clades remain controversial. This study summarizes characters of bennettitalean plants and presents new evidence for the structu...

journal_title：American journal of botany

authors： Rothwell GW,Crepet WL,Stockey RA

更新日期：2009-01-01 00:00:00

abstract：:The pathways of micro- and megagametophyte development in Agave fourcroydes (henequén) and A. angustifolia were studied. We used histology and light microscopy to observe anther ontogeny and ovary differentiation in relation to flower bud size. Both species have the same sexual reproductive strategies and gametophyte ...

journal_title：American journal of botany

authors： Piven NM,Barredo-Pool FA,Borges-Argáez IC,Herrera-Alamillo MA,Mayo-Mosqueda A,Herrera-Herrera JL,Robert ML

更新日期：2001-11-01 00:00:00

abstract：:Phylogenetic relationships and biogeography of the genus Cerastium were studied using sequences of three noncoding plastid DNA regions (trnL intron, trnL-trnF spacer, and psbA-trnH spacer). A total of 57 Cerastium taxa was analyzed using two species of the putative sister genus Stellaria as outgroups. Maximum parsimon...

journal_title：American journal of botany

authors： Scheen AC,Brochmann C,Brysting AK,Elven R,Morris A,Soltis DE,Soltis PS,Albert VA

更新日期：2004-06-01 00:00:00

abstract：PREMISE OF THE STUDY:Hybridization and polyploidization (allopolyploidy) are ubiquitous in the evolution of plants, but tracing the origins and subsequent evolution of the constituent genomes of allopolyploids has been challenging. Genome doubling greatly complicates genetic analyses, and this has long hindered investi...

journal_title：American journal of botany

authors： Buggs RJ,Renny-Byfield S,Chester M,Jordon-Thaden IE,Viccini LF,Chamala S,Leitch AR,Schnable PS,Barbazuk WB,Soltis PS,Soltis DE

更新日期：2012-02-01 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：: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：:Chloroplast DNA (cpDNA) restriction enzyme site analysis was used to test hypotheses of series and superseries affiliations of 76 taxa, representing 11 of the 13 South American series (material unavailable for two series) of wild potatoes (Solanum sect. Petota) recognized in the latest classification by Hawkes. The cl...

journal_title：American journal of botany

authors： Spooner D,Castillo R

更新日期：1997-05-01 00:00:00

abstract：:Survival and fecundity are basic components of demography and therefore have a strong influence on population dynamics. These two key parameters and their relationship are crucial to understand the evolution of life histories. It remains, however, to be empirically established how life span, fecundity, and population ...

journal_title：American journal of botany

authors： García MB,Picó FX,Ehrlén J

更新日期：2008-02-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Most studies on orchid hybrids examine separately the effects of hybridization on interactions with pollinators or with mycorrhizal fungi. Here, we simultaneously investigated both interactions in the mediterranean food-deceptive Orchis simia, O. anthropophora, and their hybrid (O. ×be...

journal_title：American journal of botany

authors： Schatz B,Geoffroy A,Dainat B,Bessière JM,Buatois B,Hossaert-McKey M,Selosse MA

更新日期：2010-08-01 00:00:00

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：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：:Additional information on the morphology of the vegetative ultimate branches of Archaeopteris roemeriana was obtained by uncovering compression specimens collected in Upper Devonian deposits in Belgium. For the first time, anisophylly, previously inferred from anatomical studies, is demonstrated on one species of the ...

journal_title：American journal of botany

authors： Fairon-Demaret M,Leponce I

更新日期：2001-04-01 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：PREMISE OF THE STUDY:Land-use change is cited as a primary driver of global biodiversity loss, with myriad consequences for species, populations, and ecosystems. However, few studies have examined its impact on species interactions, particularly pollination. Furthermore, when the effects of land-use change on pollinati...

journal_title：American journal of botany

authors： Skogen KA,Jogesh T,Hilpman ET,Todd SL,Rhodes MK,Still SM,Fant JB

更新日期：2016-11-01 00:00:00

abstract：:Gelatinous fibers (G-fibers) are the active component of tension wood. G-fibers are unlike traditional fiber cells in that they possess a thick, nonlignified gelatinous layer (G-layer) internal to the normal secondary cell wall layers. For the past several decades, the G-layer has generally been presumed to be compose...

journal_title：American journal of botany

authors： Bowling AJ,Vaughn KC

更新日期：2008-06-01 00:00:00