Aborted fruits of Opuntia microdasys (Cactaceae): insurance against reproductive failure.

abstract：:To investigate the relationship between the altitudinal distribution of Quercus laceyi and Q. sideroxyla and their physiological responses to drought, we measured relative water content (RWC), water potentials (Ψ(predawn) and Ψ(midday)), photosynthesis (A(max)), stomatal conductance (g), chlorophyll fluorescence (F(v)...

journal_title：American journal of botany

authors： Poulos HM,Goodale UM,Berlyn GP

更新日期：2007-05-01 00:00:00

abstract：:Pedilanthus coalcomanensis was described from specimens collected by George B. Hinton in 1941 but was not collected again until 1999, when we found it in a tropical deciduous forest near Tehuantepec, in Chinicuila, Michoacán, Mexico. After analyzing Hinton's original collection notes, we concluded that this is the typ...

journal_title：American journal of botany

authors： Lomelí-Sención JA,Sahagún-Godínez E

更新日期：2002-09-01 00:00:00

abstract：:In contrast to most angiosperms, in which fertilization occurs 1 or 2 days after pollination, in some plant orders, including the Fagales, fertilization is delayed from 4 days to more than 1 year, raising questions regarding why fertilization is delayed and where and how pollen tubes remain in the pistil during the de...

journal_title：American journal of botany

authors： Sogo A,Tobe H

更新日期：2006-12-01 00:00:00

abstract：:To determine the effects of density, genotype, and their interaction on individual seed mass in Raphanus sativus L., we replicated maternal and paternal families of seed across two planting densities in an experimental garden. Seeds were produced by a nested breeding design performed in the greenhouse. Among garden-ra...

journal_title：American journal of botany

authors： Mazer SJ,Wolfe LM

更新日期：1992-10-01 00:00:00

abstract：:Multiply sired fruits provide unambiguous evidence that pollen from two or more donors was deposited on a stigma and successfully fertilized ovules. Such multiple paternity within fruits can have important consequences for both parental and offspring fitness, but little is known about the frequency of multiple paterni...

journal_title：American journal of botany

authors： Mitchell RJ,Karron JD,Holmquist KG,Bell JM

更新日期：2005-05-01 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：:Iris cristata and I. lacustris differ markedly in geographic distribution, glacial history of current ranges, and ecology. We hypothesized that I. cristata, a widespread species of unglaciated regions of eastern North America, would exhibit genetic diversity typical of other widespread plant species, whereas the threa...

journal_title：American journal of botany

authors： Hannan GL,Orick MW

更新日期：2000-03-01 00:00:00

abstract：:The fossil record of aquatic flowering plants broadens our understanding of their former diversity and origins from terrestrial ancestors. This paper describes a floating aquatic monocot from 71 whole plants and several isolated leaf fragments from Upper Cretaceous oxbow lake sediments in the Dinosaur Park Formation, ...

journal_title：American journal of botany

authors： Stockey RA,Rothwell GW,Johnson KR

更新日期：2007-04-01 00:00:00

abstract：:This study examined variation in two components of acorn production. Percentage of bearing ramets (stems) and number of acorns per bearing ramet were examined in five clonal oaks in three xeric habitats of south-central peninsular Florida in relation to ramet size within and between species and vegetative associations...

journal_title：American journal of botany

authors： Abrahamson WG,Layne JN

更新日期：2002-01-01 00:00:00

abstract：:Nuclear DNA contents (4C) were estimated by Feulgen microdensitometry in 27 species of slipper orchids. These data and recent information concerning the molecular systematics of Cypripedioideae allow an interesting re-evaluation of karyotype and genome size variation among slipper orchids in a phylogenetic context. DN...

journal_title：American journal of botany

authors： Cox A,Abdelnour G,Bennett M,Leitch I

更新日期：1998-05-01 00:00:00

abstract：PREMISE OF THE STUDY:Bignoniaceae is an important component of neotropical forests and a model for evolutionary and biogeographical studies. A previous combination of molecular markers and morphological traits improved the phylogeny of the group. Here we demonstrate the value of next-generation sequencing (NGS) to asse...

journal_title：American journal of botany

authors： Firetti F,Zuntini AR,Gaiarsa JW,Oliveira RS,Lohmann LG,Van Sluys MA

更新日期：2017-10-01 00:00:00

abstract：:Sex allocation models predict that cosexuality is stabilized by high allocation to attractive structures in pollen-limited species or by high allocation to shared structures that contribute to both genders. High investment in unilateral fixed costs favor the evolution of dioecy or gender change. With these predictions...

journal_title：American journal of botany

authors： Méndez M

更新日期：2001-10-01 00:00:00

abstract：PREMISE:Hyperaccumulation of heavy metals in plants has never been documented from Central America or Mexico. Psychotria grandis, P. costivenia, and P. glomerata (Rubiaceae) have been reported to hyperaccumulate nickel in the Greater Antilles, but they also occur widely across the neotropics. The goals of this research...

journal_title：American journal of botany

authors： McCartha GL,Taylor CM,van der Ent A,Echevarria G,Navarrete Gutiérrez DM,Pollard AJ

更新日期：2019-10-01 00:00:00

abstract：:Microscopic structures (petrofilaments) may develop during palynological laboratory processing procedures that are superficially similar to secondary wall thickenings and elaters. These filaments form from angular bodies that resemble fungal spores and resin bodies. The angular bodies are a type of hydrocarbon called ...

journal_title：American journal of botany

authors： Graham A,Wood GD,Elsik WC,Speed RC

更新日期：2000-05-01 00:00:00

abstract：:The phylogenetic structure of ferns (= monilophytes) is explored here, with a special focus on the early divergences among leptosporangiate lineages. Despite considerable progress in our understanding of fern relationships, a rigorous and comprehensive analysis of the early leptosporangiate divergences was lacking. Th...

journal_title：American journal of botany

authors： Pryer KM,Schuettpelz E,Wolf PG,Schneider H,Smith AR,Cranfill R

更新日期：2004-10-01 00:00:00

abstract：:Welwitschiaceae, a family in the Gnetales, is known today from only one extant species, Welwitschia mirabilis. This species is distributed in the Namibian desert, along the western coast of southern Africa, about 10 km inland from the coast. Very little is known about the fossil record of this family. Lower Cretaceous...

journal_title：American journal of botany

authors： Dilcher DL,Bernardes-De-Oliveira ME,Pons D,Lott TA

更新日期：2005-08-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Corallodiscus is widespread across China and in adjacent countries to the west and south, with C. lanuginosus covering the entire range of the genus. Microsatellite markers will be useful to address within-complex taxonomic and biogeographic structures of this species. • METHODS AND R...

journal_title：American journal of botany

authors： Gao LM,Zhang ZR,Zhou P,Möller M,Li DZ

更新日期：2012-12-01 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：PREMISE OF THE STUDY:Evolutionary and biogeographic history, including past environmental change and diversification processes, are likely to have influenced the expansion, migration, and extinction of populations, creating evolutionary legacy effects that influence regional species pools and the composition of communi...

journal_title：American journal of botany

authors： Cavender-Bares J,Kothari S,Meireles JE,Kaproth MA,Manos PS,Hipp AL

更新日期：2018-03-01 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：:Climate changes during glacial periods have had significant effects on the present geographic distribution of plant species. To elucidate the evolutionary history of a plant species with a disjunctive distribution, we investigated the geographic distribution patterns of cpDNA haplotypes in Photinia glabra (Rosaceae) g...

journal_title：American journal of botany

authors： Aoki K,Matsumura T,Hattori T,Murakami N

更新日期：2006-12-01 00:00:00

abstract：PREMISE OF THE STUDY:Variation in demographic parameters reflects the life-history strategies of plants in response to specific environments. We aimed to investigate the intraspecific variation in life-history traits of a clonal alpine herb, Gentiana nipponica, in various snowmelt conditions. METHODS:Individual ramets...

journal_title：American journal of botany

authors： Kawai Y,Kudo G

更新日期：2018-11-01 00:00:00

abstract：:Marchantia inflexa, a dioecious thallose liverwort, is sexually dimorphic in clonal expansion traits. We used selection analyses to measure the magnitude and direction of selection on clonal fitness to uncover possible mechanisms for the maintenance of preadult sexually dimorphic characters. We planted replicates of g...

journal_title：American journal of botany

authors： Fuselier L,McLetchie N

更新日期：2002-04-01 00:00:00

abstract：:The fresh weights of suspension cultures of pear (Pyrus communis) and quince (Cydonia oblonga) increased exponentially for 30 to 40 days after subculturing. Transferring pear cultures to media in which quince cultures had grown for 10 days resulted in a 70% inhibition of callus growth. Transferring quince cultures to ...

journal_title：American journal of botany

authors： Moore R

更新日期：1986-01-01 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：:Reproductive traits of tropical tree species vary predictably in relation to successional stage, but this variation may be due to the species' phylogenetic histories rather than selective pressures imposed by regeneration requirements. Reproductive phenology, tree size at the onset of reproduction, and fecundity of 11...

journal_title：American journal of botany

authors： Davies SJ,Ashton PS

更新日期：1999-12-01 00:00:00

abstract：:Up to 22% of plant species are the result of breeding among species-hybridization-directly conflicting with the prediction that hybrids, compared to parental species, are intermediate in character and of low fitness and little consequence. Few studies, however, have compared the fitness of hybrids and parental species...

journal_title：American journal of botany

authors： Tierney DA,Wardle GM

更新日期：2008-02-01 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：:Propagule banks are assumed to be able to store considerable genetic variability. Bryophyte populations are expected to rely more heavily on stored propagules than those of seed plants due to the vulnerability of the haploid gametophyte. This reliance has important implications for the genetic structure and evolutiona...

journal_title：American journal of botany

authors： Hock Z,Szövényi P,Schneller JJ,Tóth Z,Urmi E

更新日期：2008-05-01 00:00:00

abstract：:The specific shape of the relationship between plant diversity and productivity and the causal mechanism(s) behind the observed pattern(s) are still highly debated. Recent advances suggest that the relationship depends on several environmental variables and may change with the observational scale. In this study, a mul...

journal_title：American journal of botany

authors： de Lafontaine G,Houle G

更新日期：2007-01-01 00:00:00