Abstract：
:The utility of regression and correspondence models for deducing climate from leaf physiognomy was evaluated by the comparative application of different predictive models to the same three leaf assemblages. Mean annual temperature (MAT), mean annual precipitation (MAP), and growing season precipitation (GSP) were estimated from the morphological characteristics of samples of living leaves from two extant forests and an assemblage of fossil leaves. The extant forests are located near Gainesville, Florida, and in the Florida Keys; the fossils were collected from the Eocene Clarno Nut Beds, Oregon. Simple linear regression (SLR), multiple linear regression (MLR), and canonical correspondence analysis (CCA) were used to estimate temperature and precipitation. The SLR models used only the percentage of species having entire leaf margins as a predictor for MAT and leaf size as a predictor for MAP. The MLR models used from two to six leaf characters as predictors, and the CCA used 31 characters. In comparisons between actual and predicted values for the extant forests, errors in prediction of MAT were 0.6°-5.7°C, and errors in prediction of precipitation were 6-89 cm (=6-66%). At the Gainesville site, seven models underestimated MAT and only one overestimated it, whereas at the Keys site, all eight models overestimated MAT. Precipitation was overestimated by all four models at Gainesville, and by three of them at the Keys. The MAT estimates from the Clarno leaf assemblage ranged from 14.3° to 18.8°C, and the precipitation estimates from 227 to 363 cm for MAP and from 195 to 295 cm for GSP.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Wiemann MC,Manchester SR,Dilcher DL,Hinojosa LF,Wheeler EAsubject
Has Abstractpub_date
1998-12-01 00:00:00pages
1796-802issue
12eissn
0002-9122issn
1537-2197pii
85/12/1796journal_volume
85pub_type
杂志文章abstract：PREMISE OF THE STUDY:Pollinator shifts have been implicated as a driver of divergence in angiosperms. We tested the hypothesis that there was a transition from bird- to butterfly pollination in the African genus Clivia (Amaryllidaceae) and investigated how floral traits may have been either modified or retained during ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1300363
更新日期：2014-01-01 00:00:00
abstract：PREMISE OF THE STUDY:New microsatellite primers were developed for testing genetic differentiation within Nothoceros aenigmaticus and their potential use in other Nothoceros species. The microsatellites are designed to investigate partitioning of genetic variation in a taxon with a peculiar sex allopatry in the souther...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1100392
更新日期：2012-03-01 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
pub_type： 杂志文章
doi：
更新日期：1988-01-01 00:00:00
abstract：:In a recent study (American Journal of Botany 97: 730-737), we described the first case of a tripartite association in natural conditions among a holoparasitic plant (Cytinus), its host Cistaceae species, and mycorrhizal fungi at an anatomical level. In a letter to the editor, Brundrett (American Journal of Botany 98:...
journal_title：American journal of botany
pub_type： 评论,杂志文章
doi：10.3732/ajb.1100036
更新日期：2011-04-01 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
pub_type： 杂志文章
doi：
更新日期：1998-02-01 00:00:00
abstract：PREMISE OF THE STUDY:The correct assessment of homology is an important prerequisite for reconstructing phylogenetic relationships and character evolution. Old World Papaveroideae (Papaver, Meconopsis, Roemeria, Stylomecon) show substantial diversity in gynoecium and capsule morphology. In particular, capsules can have...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1100066
更新日期：2011-08-01 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
pub_type： 杂志文章
doi：10.3732/ajb.91.10.1582
更新日期：2004-10-01 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
pub_type： 杂志文章
doi：10.3732/ajb.89.9.1485
更新日期：2002-09-01 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
pub_type： 杂志文章
doi：10.3732/ajb.1200426
更新日期：2013-08-01 00:00:00
abstract：:We provide an overview of research on climbing plants from Charles Darwin to the present day. Following Darwin's interests, this review will focus on functional perspectives including attachment mechanisms and stem structure and function. We draw attention to a number of unsolved problems inviting future research. The...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0900045
更新日期：2009-07-01 00:00:00
abstract：UNLABELLED:• PREMISE OF THE STUDY:Two ovulate conifer cones, one of which is attached terminally to a short leafy shoot, reveal the presence of a new species of Hughmillerites in the Early Cretaceous Apple Bay flora of Vancouver Island, British Columbia, Canada. This ancient conifer expands the diversity of Cupressace...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400369
更新日期：2014-12-01 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
pub_type： 杂志文章
doi：10.3732/ajb.1000032
更新日期：2010-06-01 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
pub_type： 杂志文章
doi：
更新日期：1999-12-01 00:00:00
abstract：:Cacti are a large and diverse group of stem succulents predominantly occurring in warm and arid North and South America. Chloroplast DNA sequences of the trnK intron, including the matK gene, were sequenced for 70 ingroup taxa and two outgroups from the Portulacaceae. In order to improve resolution in three major grou...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.89.2.312
更新日期：2002-02-01 00:00:00
abstract：PREMISE OF THE STUDY:The fossil record of Agathis historically has been restricted to Australasia. Recently described fossils from the Eocene of Patagonian Argentina showed a broader distribution than found previously, which is reinforced here with a new early Paleocene Agathis species from Patagonia. No previous phylo...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1127
更新日期：2018-08-01 00:00:00
abstract：:Madagasikaria andersonii is described here as a new genus and species of Malpighiaceae from Madagascar. The phylogenetic placement of Madagasikaria was estimated by using combined data from ndhF and trnL-F chloroplast sequences and phytochrome (PHYC) and ITS nuclear sequences. It forms a strongly supported clade with ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.89.4.699
更新日期：2002-04-01 00:00:00
abstract：:The amplified fragment length polymorphism (AFLP) method was used to evaluate genetic diversity and to assess genetic relationships within the section Mentha in order to clarify the taxonomy of several interspecific mint hybrids with molecular markers. To this end, genetic diversity of 62 Mentha accessions from differ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.89.12.2017
更新日期：2002-12-01 00:00:00
abstract：:Field surveys of cynipid gall-inducer occurrences on Quercus species were conducted in Florida, North Carolina, and Pennsylvania, USA. All cynipids demonstrated strong host species and organ fidelity. One result of this specialization is effective niche partitioning among cynipids. The host-association patterns of the...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-08-01 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
pub_type： 杂志文章
doi：
更新日期：2000-09-01 00:00:00
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
pub_type： 杂志文章
doi：10.3732/ajb.94.5.809
更新日期：2007-05-01 00:00:00
abstract：PREMISE OF THE STUDY:Climate change models for California predict a warmer, drier future, potentially resulting in shorter growing seasons. If phenotypic differences between closely related species currently distributed across a moisture and temperature gradient represent adaptations to their abiotic environment, then ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1500108
更新日期：2016-01-01 00:00:00
abstract：:Recent discoveries of fossil reproductive structures from deposits of the Raritan Formation in New Jersey (Turonian, Upper Cretaceous, ~90 million years BP) include a previously undescribed representative of the Order Capparales. The fossils are usually charcoalified with three-dimensional structure and excellent anat...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-07-01 00:00:00
abstract：PREMISE OF THE STUDY:Plants adjust their phenology in response to seasonal cues experienced both by their parents and by themselves, and coordinating responses to these cues is necessary for expressing adaptive phenology. We investigated how cues are integrated across time to influence an important progeny phenotype, i...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1600389
更新日期：2017-04-01 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
pub_type： 杂志文章
doi：10.3732/ajb.90.11.1645
更新日期：2003-11-01 00:00:00
abstract：PREMISE OF THE STUDY:Endophytic fungi are common inhabitants of cool-season grasses that can affect host growth and reproduction. One prerequisite for the expected coevolution between symbionts is that there exist variable effects of the endosymbiont on its host in different environments. Here, the impact of endophytes...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1000226
更新日期：2011-05-01 00:00:00
abstract：:Bennettitales is an extinct group of seed plants with reproductive structures that are similar in some respects to both Gnetales and angiosperms, but systematic relationships among the three clades remain controversial. This study summarizes characters of bennettitalean plants and presents new evidence for the structu...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0800209
更新日期：2009-01-01 00:00:00
abstract：:Floral characteristics such as morphology and flower color have been interpreted as adaptive traits that evolved through selective pressures generated by pollinators. Differences among populations in the expression of floral characters could result from natural selection for their adaptive value to local conditions. W...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.90.3.377
更新日期：2003-03-01 00:00:00
abstract：UNLABELLED: PREMISE OF THE STUDY:Microsatellite primers were developed in the introduced shrub Rhamnus cathartica L., to investigate potential hybridization events with related taxa as a stimulus of invasive spread. • METHODS AND RESULTS:Using a non-radioactive protocol, 15 primer sets were identified in North Americ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0900394
更新日期：2010-03-01 00:00:00
abstract：:There have been three periods of significant discovery in the exploration of fern and lycophyte genetics. First, during the 1930s, Andersson-Kottö conducted crossing studies on ferns. The publication of Manton's magnum opus on fern chromosomes in 1950 stimulated the second. The third emerged from Klekowski's 1973 Amer...
journal_title：American journal of botany
pub_type： 杂志文章,评审
doi：10.3732/ajb.1400317
更新日期：2014-12-01 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
pub_type： 杂志文章
doi：10.1002/j.1537-2197.1986.tb09673.x
更新日期：1986-01-01 00:00:00
