Is the anthophyte hypothesis alive and well? New evidence from the reproductive structures of Bennettitales.

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：:We investigated patterns of fruit and seed production on inflorescences of a population of Pancratium maritimum in northwest Spain over a 2-yr period. Initial findings showed that the earliest opening flowers on an inflorescence are more likely to set fruit and produce more seeds than later opening flowers and that th...

journal_title：American journal of botany

authors： Medrano M,Guitián P,Guitián J

更新日期：2000-04-01 00:00:00

abstract：PREMISE OF THE STUDY:The presence or absence of a functional copy of a plastid gene may reflect relaxed selection, and may be phylogenetically significant, reflecting shared ancestry. In some liverworts, the plastid gene cysA is a pseudogene (inferred to be nonfunctional). We surveyed 63 liverworts from all major clade...

journal_title：American journal of botany

authors： Wickett NJ,Forrest LL,Budke JM,Shaw B,Goffinet B

更新日期：2011-08-01 00:00:00

abstract：PREMISE OF THE STUDY:Climate cycles of the Quaternary have impacted plants at a global scale, leaving behind a complex genetic legacy. Species of the northern Rocky Mountains of North America were exposed to more uniform glacial patterns than the central and southern ranges, where synergistic relationships between temp...

journal_title：American journal of botany

authors： Fuller RS,McGlaughlin ME

更新日期：2019-03-01 00:00:00

abstract：:For more than a century, the common ancestor of flowering plants was thought to have had a seven-celled, eight-nucleate Polygonum-type female gametophyte. It is now evident that not one, but in fact three, patterns of female gametophyte development and mature structure characterize the common ancestors of the four mos...

journal_title：American journal of botany

authors： Friedman WE,Ryerson KC

更新日期：2009-01-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Invasive plant species threaten native plants in multiple ways, one of which is genetic assimilation through hybridization. However, information regarding hybridization between related alien and native plant species is generally lacking. In Hawaii, the invasive Central American species...

journal_title：American journal of botany

authors： Knope ML,Pender RJ,Crawford DJ,Wieczorek AM

更新日期：2013-06-01 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：PREMISE OF THE STUDY:Inclusion of fossils in phylogenetic analyses is necessary in order to construct a comprehensive "tree of death" and elucidate evolutionary history of taxa; however, such incorporation of fossils in phylogenetic reconstruction is dependent on the availability and interpretation of extensive morphol...

journal_title：American journal of botany

authors： Smith SY,Iles WJD,Benedict JC,Specht CD

更新日期：2018-08-01 00:00:00

abstract：PREMISE OF THE STUDY:Population genetic structuring over limited timescales is commonly viewed as a consequence of spatial constraints. Indirect approaches have recently revealed reproductive isolation resulting from flowering time (so-called isolation by time, IBT). Since phenological processes can be subject to selec...

journal_title：American journal of botany

authors： Daïnou K,Laurenty E,Mahy G,Hardy OJ,Brostaux Y,Tagg N,Doucet JL

更新日期：2012-09-01 00:00:00

abstract：:This paper reports the frequency of spontaneous amphiploids or neopolyploids in experimental interspecific hybrids in two annual sections of Gilia (Polemoniaceae, sects. Arachnion and Gilia, x = 9). In each section the species were intercrossed in numerous hybrid combinations to obtain an array of F1 hybrid types; sev...

journal_title：American journal of botany

authors： Grant V

更新日期：2002-08-01 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：:When more pollen is present on stigmas than needed to fertilize all ovules, selection among pollen grains may occur due to effects of both pollen donors and maternal plants. We asked whether increasing plant age and flower age, two changes in maternal condition, altered the pattern of seed paternity after mixed pollin...

journal_title：American journal of botany

authors： Marshall DL,Reynolds J,Abrahamson NJ,Simpson HL,Barnes MG,Medeiros JS,Walsh S,Oliveras DM,Avritt JJ

更新日期：2007-03-01 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：:In a wet oligotrophic meadow located in the Czech Republic, a factorial experiment with treatments consisting of fertilization, mowing, and removal of the dominant species (Molinia caerulea) was established in 1994. In 1997 Holcus lanatus, Molinia caerulea, Potentilla erecta, Prunella vulgaris, and Ranunculus auricomu...

journal_title：American journal of botany

authors： Titus JH,Leps J

更新日期：2000-03-01 00:00:00

abstract：PREMISE OF THE STUDY:During the interactions between a parasitic plant and its host, the parasite affects its host morphologically, anatomically, and physiologically, yet there has been little focus on the effect of hosts on the parasite. Here, the functional interactions between the hemiparasitic mistletoe Psittacanth...

journal_title：American journal of botany

authors： Cocoletzi E,Angeles G,Ceccantini G,Patrón A,Ornelas JF

更新日期：2016-06-01 00:00:00

abstract：UNLABELLED:• PREMISE OF THE STUDY:The ability to respond to environmental change via phenotypic plasticity may be important for plants experiencing disturbances such as climate change and plant invasion. Responding to belowground competition through root plasticity may allow native plants to persist in highly invaded ...

journal_title：American journal of botany

authors： Phillips AJ,Leger EA

更新日期：2015-01-01 00:00:00

abstract：:Long-distance transplantation of seed material as done in restoration programs has raised concerns about the risks associated with the introduction of maladapted genotypes that may hybridize with neighboring native conspecifics and decrease local population fitness (outbreeding depression). We studied the consequences...

journal_title：American journal of botany

authors： Crémieux L,Bischoff A,Müller-Schärer H,Steinger T

更新日期：2010-01-01 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：: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：:Wind is a major ecological factor for plants and a major economical factor for forestry. Mechanical analyses have revealed that the multimodal dynamic behavior of trees is central to wind-tree interactions. Moreover, the trunk and branches influence dynamic modes, both in frequency and location. Because of the complex...

journal_title：American journal of botany

authors： Rodriguez M,Langre Ed,Moulia B

更新日期：2008-12-01 00:00:00

abstract：PREMISE OF THE STUDY:Geographic differences in flower visitor assemblages might lead to among-population differences in the magnitude and pattern of floral integration. However, the role of current pollinator visitation in shaping the magnitude and pattern of floral trait correlations is still controversial. METHODS:W...

journal_title：American journal of botany

authors： Lázaro A,Santamaría L

更新日期：2016-02-01 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：:In rainforests, trunk size, strength, crown position, and geometry of a tree affect light interception and the likelihood of mechanical failure. Allometric relationships of tree diameter, wood density, and crown architecture vs. height are described for a diverse range of rainforest trees in Brunei, northern Borneo. T...

journal_title：American journal of botany

authors： Osunkoya OO,Omar-Ali K,Amit N,Dayan J,Daud DS,Sheng TK

更新日期：2007-12-01 00:00:00

abstract：:• Premise of the study: The mechanical properties of a plant are key variables governing the interaction between the plant and its environment. Thus, measuring variables such as the flexural rigidity (bending) of a plant element is necessary to understand and predict the plant-flow interaction. However, plant elements...

journal_title：American journal of botany

authors： Henry PY

更新日期：2014-06-01 00:00:00

abstract：PREMISE OF THE STUDY:A prevailing hypothesis in forest succession is that shade-tolerant species grow more slowly than shade-intolerant species, across light conditions, because they prioritize carbon (C) allocation to storage. We examined this hypothesis in a confamilial pair of species, including one of the fastest-g...

journal_title：American journal of botany

authors： Piper FI,Sepúlveda P,Bustos-Salazar A,Zúñiga-Feest A

更新日期：2017-05-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Verbenaceae consist of trees, shrubs, lianas, and herbs distributed primarily in Latin America, where they occur in a wide array of ecosystems. A second center of diversity exists in Africa. Competing morphology-based classifications that rely on different traits conflict in significan...

journal_title：American journal of botany

authors： Marx HE,O'Leary N,Yuan YW,Lu-Irving P,Tank DC,Múlgura ME,Olmstead RG

更新日期：2010-10-01 00:00:00

abstract：:Dispersal is an important life history component. Seed settling velocity may be a useful surrogate for the measurement of dispersal ability in wind-dispersed plants, particularly those whose seeds have plumose dispersal structures. I measured settling velocities on seeds of eight species of Asteraceae, including annua...

journal_title：American journal of botany

authors： Andersen MC

更新日期：1992-10-01 00:00:00

abstract：UNLABELLED: PREMISE OF THE STUDY:Polyploid speciation has been important in plant evolution. However, the conditions that favor the origination and persistence of polyploids are still not well understood. Here, we examine origins of 16 polyploid species in Mentzelia section Trachyphytum. • METHODS:We used phylogeny r...

journal_title：American journal of botany

authors： Brokaw JM,Hufford L

更新日期：2010-09-01 00:00:00

abstract：PREMISE OF THE STUDY:Populations of heterostylous species are characterized by two or three floral morphs with reciprocal positioning of stigmas and anthers. Theoretical models predict equal morph frequencies (isoplethy) when disassortative mating is prevalent in populations, but biased morph ratios may occur when vari...

journal_title：American journal of botany

authors： Ferrero V,Barrett SC,Rojas D,Arroyo J,Navarro L

更新日期：2017-01-01 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