Complex origins of breadfruit (Artocarpus altilis, Moraceae): implications for human migrations in Oceania.

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：:The degree to which plants self-fertilize may impact their potential for genetic adaptation. Given that the mating system influences genetic processes within and among populations, the mating system could limit or promote local adaptation. I conducted a literature survey of published reciprocal transplant experiments ...

journal_title：American journal of botany

authors： Hereford J

更新日期：2010-02-01 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：: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：UNLABELLED: PREMISE OF THE STUDY:A mixture of outcrossing and selfing is often observed in plant populations. Although mixed mating is ubiquitous, it has several potential evolutionary explanations. Mixed mating may be actively maintained by selection, passively determined by the pollination environment, or a transiti...

journal_title：American journal of botany

authors： Busch JW,Herlihy CR,Gunn L,Werner WJ

更新日期：2010-06-01 00:00:00

abstract：:Axillary meristems play a fundamental role in inflorescence architecture. Maize (Zea mays) inflorescences are highly branched panicles because of the production of multiple types of axillary meristems. We used auxin transport inhibitors to show that auxin transport is required for axillary meristem initiation in the m...

journal_title：American journal of botany

authors： Wu X,McSteen P

更新日期：2007-11-01 00:00:00

abstract：PREMISE:Despite the fast pace of exploration of the patterns and processes influencing Neotropical plant hyperdiversity, the taxa explored are mostly from large groups that are widely distributed, morphologically diverse, or economically important. Vochysiaceae is an example of an undersampled taxon, providing an excel...

journal_title：American journal of botany

authors： Gonçalves DJP,Shimizu GH,Ortiz EM,Jansen RK,Simpson BB

更新日期：2020-07-01 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：: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：:Plant xylem must balance efficient delivery of water to the canopy against protection from air entry into the conduits via air-seeding. We investigated the relationship between tracheid allometry, end wall pitting, safety from air-seeding, and the hydraulic efficiency of conifer wood in order to better understand the ...

journal_title：American journal of botany

authors： Pittermann J,Sperry JS,Hacke UG,Wheeler JK,Sikkema EH

更新日期：2006-09-01 00:00:00

abstract：:Plant tropisms play a fundamental role in shaping the growth form of plants, and these fascinating movements are the focus of this thematic issue of the American Journal of Botany. The issue includes 16 reviews of the current literature and eight original manuscripts written by a diverse group of international experts...

journal_title：American journal of botany

authors： Wyatt SE,Kiss JZ

更新日期：2013-01-01 00:00:00

abstract：:Studies of developmental stability can provide insights into the amount of genetic or environmental stress experienced by individuals or populations. In the present study, we used young plants of Acer platanoides (Norway maple) and Betula pendula (silver birch), two distantly related tree species with widely different...

journal_title：American journal of botany

authors： Black-Samuelsson S,Andersson S

更新日期：2003-08-01 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：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

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

更新日期：2015-10-01 00:00:00

abstract：:Leaf habit correlates with multiple physiological traits. Understanding ecophysiology is therefore dependent on knowledge of leaf habit. A variety of leaf habits exists within forest understory plant communities. Oxalis acetosella is one such understory plant and has long been considered a wintergreen, meaning that it...

journal_title：American journal of botany

authors： Tessier JT

更新日期：2004-09-01 00:00:00

abstract：PREMISE:The genus Arisaema (Araceae) has rapidly diversified in Japan, and multiple species often coexist in the field. Although Japanese Arisaema species hybridize from artificial crossing, hybrid individuals are rare in mixed populations; suggesting the presence of effective pre-pollination barriers. We examined the ...

journal_title：American journal of botany

authors： Matsumoto TK,Miyazaki Y,Sueyoshi M,Senda Y,Yamada K,Hirobe M

更新日期：2019-12-01 00:00:00

abstract：:The selective maintenance of gynodioecy depends on the relative fitness of the male-sterile (female) and hermaphroditic morphs. Females may compensate for their loss of male fitness by reallocating resources from male function (pollen production and pollinator attraction) to female function (seeds and fruits), thus in...

journal_title：American journal of botany

authors： Williams CF,Kuchenreuther MA,Drew A

更新日期：2000-05-01 00:00:00

abstract：:It is often suggested that traits will be integrated, either because of pleiotropy or because natural selection may favor suites of integrated traits. Plant responses to different environments can provide evidence of such integration. We grew Mercurialis annua plants in high-density stands in high irradiance, in neutr...

journal_title：American journal of botany

authors： Sleeman JD,Dudley SA,Pannell JR,Barrett SC

更新日期：2002-09-01 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：: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：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

authors： Sanders WB

更新日期：2014-11-01 00:00:00

abstract：:The eudicot order Malpighiales contains ∼16000 species and is the most poorly resolved large rosid clade. To clarify phylogenetic relationships in the order, we used maximum likelihood, Bayesian, and parsimony analyses of DNA sequence data from 13 gene regions, totaling 15604 bp, and representing all three genomic com...

journal_title：American journal of botany

authors： Wurdack KJ,Davis CC

更新日期：2009-08-01 00:00:00

abstract：PREMISE OF THE STUDY:Identifying recently diverged taxa can be useful for studying the process of speciation. Ipomoea lacunosa and I. cordatotriloba, along with a putative homoploid hybrid, I. ×leucantha, are closely related taxa, which are promising for investigating the early stages of speciation. The objectives of t...

journal_title：American journal of botany

authors： Duncan TM,Rausher MD

更新日期：2013-11-01 00:00:00

abstract：:Tribe Macadamieae (91 spp., 16 genera; Proteaceae) is widespread across the southern hemisphere on all major fragments of Gondwana except New Zealand and India. Macadamia is cultivated outside its natural range as a "nut" crop (notably in Hawaii, where it is the principal orchard crop). We sampled seven DNA regions an...

journal_title：American journal of botany

authors： Mast AR,Willis CL,Jones EH,Downs KM,Weston PH

更新日期：2008-07-01 00:00:00

abstract：:Individual plants of Asclepias exaltata (Asclepiadaceae) typically express an unusual self-incompatibility system under single-gene control. Hand-pollinations performed in six natural populations detected occasional self-fertile plants. The frequency of self-fertile individuals ranged from 0 to 34.0% and differed sign...

journal_title：American journal of botany

authors： Lipow SR,Broyles SB,Wyatt R

更新日期：1999-08-01 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：: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：:Inbreeding depression is a critical factor countering the evolution of inbreeding and thus potentially shaping the evolution of plant sexual systems. Current theory predicts that inbreeding depression could have important evolutionary consequences, even in haploid-dominant organisms. To date, no data have been reporte...

journal_title：American journal of botany

authors： Taylor PJ,Eppley SM,Jesson LK

更新日期：2007-11-01 00:00:00

abstract：PREMISE OF THE STUDY:Mixotrophy is a strategy whereby plants acquire carbon both through photosynthesis and heterotrophic exploitation of mycorrhizal fungi. In Euro-American Pyroleae species studied hitherto, heterotrophy levels vary according to species, sites of study, and possibly light conditions. We investigated m...

journal_title：American journal of botany

authors： Matsuda Y,Shimizu S,Mori M,Ito S,Selosse MA

更新日期：2012-07-01 00:00:00

abstract：:We developed an improved cytological protocol for producing high quality, light microscope images of plant meiotic chromosomes. Because the technique works on species with small genomes and thick microsporocyte cell walls, it should be useful for studying the wild relatives of Arabidopsis and other eudicots with small...

journal_title：American journal of botany

authors： Stronghill PE,Hasenkampf CA

更新日期：2007-12-01 00:00:00