Endosymbiosis and population differentiation in wild and cultivated Lolium perenne (Poaceae).

abstract：PREMISE OF THE STUDY:Tetraena simplex is an independently evolved C4 species in the Zygophylloideae (Zygophyllaceae) and a characteristic forb of saline flats in hot and sandy desert habitats. During early ontogeny, the species had a morphological shift from planar cotyledons (dorsiventral symmetry) to terete, succulen...

journal_title：American journal of botany

authors： Muhaidat R,McKown AD,Al Zoubi M,Bani Domi Z,Otoum O

更新日期：2018-05-01 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 Strait of Gibraltar is the most important barrier disconnecting the landmasses of Europe and Africa on the western Mediterranean extreme. Carex helodes is a wind-pollinated species endemic to the western Mediterranean. Because molecular and cytogenetic data allow the inference of its evolutionary history, we analy...

journal_title：American journal of botany

authors： Escudero M,Vargas P,Valcárcel V,Luceño M

更新日期：2008-06-01 00:00:00

abstract：:We launched imbibed seeds and seedlings of Zea mays into outer space aboard the space shuttle Columbia to determine the influence of microgravity on 1) root-cap regeneration, and 2) the distribution of amyloplasts and endoplasmic reticulum (ER) in the putative statocytes (i.e., columella cells) of roots. Decapped roo...

journal_title：American journal of botany

authors： Moore R,McClelen CE,Fondren WM,Wang CL

更新日期：1987-01-01 00:00:00

abstract：PREMISE OF THE STUDY:Self-incompatibility (SI) is a mechanism that prevents inbreeding in many plant species. The mutational breakdown of SI occurs frequently, yet relatively little is known about the evolutionary steps involved in the progressive loss of pistil and pollen SI function. METHODS:In Solanaceae, SI is the...

journal_title：American journal of botany

authors： Markova DN,Petersen JJ,Qin X,Short DR,Valle MJ,Tovar-Méndez A,McClure BA,Chetelat RT

更新日期：2016-10-01 00:00:00

abstract：:In spite of the ecological and economic importance of temperate bamboos, relatively little is known about their population biology or evolutionary history. Recently, hybridization has emerged as a potential source of diversity in this group, as well as an underlying cause of taxonomic problems. As part of a broader ph...

journal_title：American journal of botany

authors： Triplett JK,Oltrogge KA,Clark LG

更新日期：2010-03-01 00:00:00

abstract：:The origin of polyploid Bromus species of section Genea was investigated using molecular data. This group of annual species native from the Old-World is composed of three diploids, two tetraploids, one hexaploid, and one octoploid. Molecular cloning, sequencing, and phylogenetic analyses were performed on several acce...

journal_title：American journal of botany

authors： Fortune PM,Pourtau N,Viron N,Ainouche ML

更新日期：2008-04-01 00:00:00

abstract：:The cell division pattern in the apical meristem of Psilotum nudum was examined using epi-illumination microscopy and a paraffin method. In the subterranean axis, about half of the derivative cells of the apical cell produce tetrahedral daughter apical cells by the first three or more oblique divisions. Roughly half o...

journal_title：American journal of botany

authors： Takiguchi Y,Imaichi R,Kato M

更新日期：1997-05-01 00:00:00

abstract：:Floral morphology of the 13 species of Moringa ranges from actinomorphic flowers with little hypanthium to highly zygomorphic flowers with well-developed hypanthia. Scanning electron and light microscopy were used to identify ontogenetic differences among two actinomorphic and eight zygomorphic species. All species sh...

journal_title：American journal of botany

authors： Olson ME

更新日期：2003-01-01 00:00:00

abstract：:Despite their ecological significance, parasitic plants face more conservation challenges than do autotrophic plants. This is especially true for the groups that include weedy or invasive species such as Cuscuta. While approximately half of the Cuscuta (dodders) species may require conservation measures, the genus as ...

journal_title：American journal of botany

authors： Costea M,Stefanovic S

更新日期：2009-09-01 00:00:00

abstract：:In turnip mitochondria the cox2 gene is partially contained within a 2-kb (kilobase) direct repeat that is the site of homologous recombination events that generate subgenomic molecules. Because of its partial presence within the direct repeat, the turnip cox2 gene exists in four genomic contexts, two on the master ch...

journal_title：American journal of botany

authors： Dong F,Wilson K,Makaroff C

更新日期：1998-02-01 00:00:00

abstract：:We investigated the possible effect of recent (1927-1995) increases in the concentration of atmospheric CO2 on the stomatal densities of leaves of a wide range of tree, shrub, and herb species (N = 60) by making new measurements for comparison with corresponding data reported by E. J. Salisbury in 1927--a time when ic...

journal_title：American journal of botany

authors： Beerling D,Kelly C

更新日期：1997-11-01 00:00:00

abstract：:Biogeographical patterns and diversification processes in Andean and Patagonian flora are not yet well understood. Calceolaria is a highly diversified genus of these areas, representing one of the most specialized plant-pollinator systems because flowers produce nonvolatile oils, a very unusual floral reward. Phylogen...

journal_title：American journal of botany

authors： Cosacov A,Sérsic AN,Sosa V,De-Nova JA,Nylinder S,Cocucci AA

更新日期：2009-12-01 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：:Gas exchange was measured in two subalpine herbs during alternating periods of sun and shade that simulated natural cloud patterns. Stomatal conductance (g) in the subalpine herb Helianthella quinquenervis was reduced by as much as 75% during 5-min shade periods that ranged in photosynthetic photon flux density (PPFD)...

journal_title：American journal of botany

authors： Knapp AK,Smith WK

更新日期：1990-02-01 00:00:00

abstract：:In a detailed analysis of how limited seed dispersal can create spatial structuring of genetic variation, several nuclear microsatellites were assayed in seedlings from two forests of Pinus strobus, one old growth (OG) and the other (second site, SS) logged in ca. 1900. By using loci with a large number of alleles and...

journal_title：American journal of botany

authors： Walter R,Epperson BK

更新日期：2004-04-01 00:00:00

abstract：:Breakdown of genetically enforced self-incompatibility (SI), an extremely common and important evolutionary transition in plants, has conventionally been conceived as a qualitative rather than a quantitative change. We evaluated qualitative and quantitative variation in SI for four populations of Witheringia solanacea...

journal_title：American journal of botany

authors： Stone JL,Sasuclark MA,Blomberg CP

更新日期：2006-04-01 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：: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：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：:Phylogenetic relationships of 38 species of the Alibertia group (Rubiaceae) and two outgroup species were investigated using the nuclear ribosomal 5S nontranscribed spacer (5S-NTS) and the internal transcribed spacers (ITS). Analysis of the data sets separately and in combination resulted in several well-supported and...

journal_title：American journal of botany

authors： Persson C

更新日期：2000-07-01 00:00:00

abstract：:We studied 15 riparian and upland Sonoran desert species to evaluate how the limitation of xylem pressure (Ψ(x)) by cavitation corresponded with plant distribution along a moisture gradient. Riparian species were obligate riparian trees (Fraxinus velutina, Populus fremontii, and Salix gooddingii), native shrubs (Bacch...

journal_title：American journal of botany

authors： Pockman WT,Sperry JS

更新日期：2000-09-01 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：: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：:The geographic distribution of diploid and tetraploid cytotypes and cpDNA haplotypes throughout the entire range of Aucuba japonica was investigated. We measured relative genome size using flow cytometry and sequenced two cpDNA intergenic regions, atpB-rbcL and psbA-trnH (GUG). Two haplotypes include both diploids and...

journal_title：American journal of botany

authors： Ohi T,Kajita T,Murata J

更新日期：2003-11-01 00:00:00

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

authors： Ghyselen C,Bonte D,Brys R

更新日期：2015-12-01 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：:Correlations were examined between habitat characters and clonal structures determined by the RAPD (random amplified polymorphic DNA) assay in five populations of Oryza rufipogon in China. Nine of 175 decameric primers were used in the study because they reproducibly amplified polymorphisms. The extent of clonality to...

journal_title：American journal of botany

authors： Xie ZW,Lu YQ,Ge S,Hong DY,Li FZ

更新日期：2001-06-01 00:00:00

abstract：PREMISE OF THE STUDY:Ferns and lycophytes are the only extant land plants with two free-living generations (sporophytes and gametophytes); hence, a single species may have two different distributions. The distribution of the gametophytes of most fern species, which are much smaller in size than sporophytes, are almost ...

journal_title：American journal of botany

authors： Ebihara A,Yamaoka A,Mizukami N,Sakoda A,Nitta JH,Imaichi R

更新日期：2013-04-01 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