Cryptic goldfields: a molecular phylogenetic reinvestigation of Lasthenia californica sensu lato and close relatives (Compositae: Heliantheae sensu lato).

abstract：UNLABELLED: PREMISE OF THE STUDY:Sphagnum dominates vast expanses of wetland habitats throughout the northern hemisphere and species delimitation within the genus is important because floristic changes associated with a warming global climate may have measureable impacts on large-scale ecological processes. Most north...

journal_title：American journal of botany

authors： Shaw AJ,Shaw B,Johnson MG,Higuchi M,Arikawa T,Ueno T,Devos N

更新日期：2013-06-01 00:00:00

abstract：:We used the chloroplast gene ndhF to reconstruct the phylogeny of the moonseed family (Menispermaceae), a morphologically diverse and poorly known cosmopolitan family of dioecious, primarily climbing plants. This study includes a worldwide sample of DNA sequences for 88 species representing 49 of the 70 genera of all ...

journal_title：American journal of botany

authors： Ortiz Rdel C,Kellogg EA,Werff HV

更新日期：2007-08-01 00:00:00

abstract：:Oxalate crystals are very common in angiosperms, but few descriptions of their macropattern (crystal types, their tissue distribution, and development) exist. Because unusually large prismatic crystals and druses, are known from pomegranate, we traced the development of crystal macropattern in various-aged leaf sample...

journal_title：American journal of botany

authors： Lersten NR,Horner HT

更新日期：2005-12-01 00:00:00

abstract：:Detailed investigations on Lower Cretaceous Ephedra L. fossils (Gnetopsida) reveal morphological characters similar to those of extant Ephedra rhytidosperma Pachomova, including articulate branches with many fine longitudinal striations, a dichasial branching pattern, uni- or bi-ovulate cones with paired bracts, cones...

journal_title：American journal of botany

authors： Yang Y,Geng BY,Dilcher DL,Chen ZD,Lott TA

更新日期：2005-02-01 00:00:00

abstract：PREMISE OF THE STUDY:Microsatellite markers were developed for the dove tree, Davidia involucrata (Cornaceae), a Tertiary relict currently endemic to China, to investigate its population genetics and phylogeography. METHODS AND RESULTS:Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol,...

journal_title：American journal of botany

authors： Tao C,Yang Z,Lu R,Liu T,Chen S,Ji Y

更新日期：2012-03-01 00:00:00

abstract：PREMISE:Understanding plant hydraulic functioning and water balance during drought has become key in predicting species survival and recovery. However, there are few insightful studies that couple physiological and morphological attributes for many ecosystems, such as the vulnerable Tropical Montane Cloud Forests (TMCF...

journal_title：American journal of botany

authors： Berry ZC,Espejel X,Williams-Linera G,Asbjornsen H

更新日期：2019-10-01 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：:The relationship between pollen and progeny performance has been a subject of many studies but the evidence for pollen-tube growth rate as an indicator of progeny fitness is equivocal. We used an anemophilous tree, Betula pendula, to examine the relationship between pollen-tube growth rate and seed and seedling perfor...

journal_title：American journal of botany

authors： Pasonen HL,Pulkkinen P,Käpylä M

更新日期：2001-05-01 00:00:00

abstract：:Clarkia (Onagraceae) is a genus of 42 annual species, mostly native to California, that has served as a model for many studies of plant evolutionary biology, particularly morphological, cytological, and genetic divergence; reproductive isolation; and speciation. Section Sympherica is the largest section with eight dip...

journal_title：American journal of botany

authors： Ford VS,Gottlieb LD

更新日期：2003-02-01 00:00:00

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

authors： Nikkeshi A,Kurimoto D,Ushimaru A

更新日期：2015-12-01 00:00:00

abstract：PREMISE OF THE STUDY:We isolated and characterized microsatellite markers for the California poppy, Eschscholzia californica, which is an invasive species in central Chile. METHODS AND RESULTS:A total of eight polymorphic and six monomorphic loci were developed for the species. Between one and 12 alleles were observed...

journal_title：American journal of botany

authors： Véliz D,Gauci R,Bustamante RO

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：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：: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: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 ultrastructure of Typha latifolia pollen was examined as a function of pollen moisture content and incubation temperature, in order to identify possible lesions induced by imbibitional chilling. A syndrome of structural traits was found which characterizes damaged grains. Compared to viable grains, the protoplas...

journal_title：American journal of botany

authors： Sack FD,Leopold AC,Hoekstra FA

更新日期：1988-01-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Taxonomic groups have often been recognized on the basis of geographic distinctions rather than accurately representing evolutionary relationships. This has been particularly true for temperate and tropical members from the same family. Polygonaceae exemplifies this problem, wherein th...

journal_title：American journal of botany

authors： Burke JM,Sanchez A,Kron K,Luckow M

更新日期：2010-08-01 00:00:00

abstract：PREMISE OF THE STUDY:The opuntias (nopales, prickly pears) are not only culturally, ecologically, economically, and medicinally important, but are renowned for their taxonomic difficulty due to interspecific hybridization, polyploidy, and morphological variability. Evolutionary relationships in these stem succulents ha...

journal_title：American journal of botany

authors： Majure LC,Puente R,Griffith MP,Judd WS,Soltis PS,Soltis DE

更新日期：2012-05-01 00:00:00

abstract：:The recent consensus that Amborellaceae, Nymphaeales, and Austrobaileyales form the three earliest-diverging lineages of angiosperms has led comparative biologists to reconsider the origin and early developmental evolution of the angiosperm seven-celled/eight-nucleate (Polygonum-type) female gametophyte. Illicium mexi...

journal_title：American journal of botany

authors： Williams JH,Friedman WE

更新日期：2004-03-01 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：: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：:Cleistogamous capitula formed by Centaurea melitensis display a number of morphological and functional changes with respect to chasmogamous capitula that ensure self-fertilization. Because no studies have hitherto addressed the evolution of cleistogamy in Asteraceae, it was considered useful to ascertain whether these...

journal_title：American journal of botany

authors： Porras R,Muñoz JM

更新日期：2000-07-01 00:00:00

abstract：:Tacca, a genus of tropical herbs, possesses near black flowers, conspicuous involucral bracts and whisker-like filiform bracteoles. These features have been assumed to function as a "deceit syndrome" in which reproductive structures resemble decaying organic material attracting flies that facilitate cross-pollination ...

journal_title：American journal of botany

authors： Zhang L,Barrett SC,Gao JY,Chen J,Cole WW,Liu Y,Bai ZL,Li QJ

更新日期：2005-03-01 00:00:00

abstract：:The cacti are well-known desert plants, widely recognized by their specialized growth form and essentially leafless condition. Pereskia, a group of 17 species with regular leaf development and function, is generally viewed as representing the "ancestral cactus," although its placement within Cactaceae has remained unc...

journal_title：American journal of botany

authors： Edwards EJ,Nyffeler R,Donoghue MJ

更新日期：2005-07-01 00:00:00

abstract：:Biparental inbreeding is thought to be a common feature of plant populations with restricted pollen dispersal. It is generally assumed that the inbreeding depression frequently observed to accompany self-fertilization can be extrapolated to the lesser degrees of consanguinity involved in biparental inbreeding, but thi...

journal_title：American journal of botany

authors： Heywood JS

更新日期：1993-05-01 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：PREMISE OF THE STUDY:Several members of Selaginella are renowned for their ability to survive extreme drought and "resurrect" when conditions improve. Many of these belong to subgenus Tetragonostachys, a group of ∼45 species primarily found in North and Central America, with substantial diversity in the Sonoran and Chi...

journal_title：American journal of botany

authors： Arrigo N,Therrien J,Anderson CL,Windham MD,Haufler CH,Barker MS

更新日期：2013-08-01 00:00:00

abstract：:Breadfruit (Artocarpus altilis, Moraceae), a traditional starch crop in Oceania, has enjoyed legendary status ever since its role in the infamous mutiny aboard the H.M.S. Bounty in 1789, yet its origins remain unclear. Breadfruit's closest relatives are A. camansi and A. mariannensis. DNA fingerprinting data (AFLP, am...

journal_title：American journal of botany

authors： Zerega NJ,Ragone D,Motley TJ

更新日期：2004-05-01 00:00:00

abstract：PREMISE OF THE STUDY:Species differ in their temperature germination niche. Populations of a species may similarly differ across the distribution range of the species. Anticipating the impacts of climate variability and change requires understanding the differential sensitivity to germination temperature among and with...

journal_title：American journal of botany

authors： Chamorro D,Luna B,Moreno JM

更新日期：2017-01-01 00:00:00

abstract：:The shoot apical meristem (SAM) produces stem and initiates leaves. Its structure is maintained despite a continuous flow of cells basipetally from the distal portion of the meristem. The apoplasm and symplasm are the obvious means of cell integration, and their role in chemical cell-to-cell signaling is known. Howeve...

journal_title：American journal of botany

authors： Kwiatkowska D

更新日期：2004-09-01 00:00:00