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 in mind, I studied sexual mass allocation at flowering in the monoecious Arum italicum (Araceae) and compared it with information available for its sex labile relative Arisaema dracontium. In A. italicum, 68% of biomass was allocated to structures believed to be involved in pollinator attraction and capture. This allocation pattern contrasts with that of Arisaema dracontium, in which 70% of biomass was allocated to scape, considered to be a unilateral fixed cost. The importance of attractive structures in A. italicum was further supported by a disproportionate increased allocation, in larger inflorescences, to the appendix (an attractive structure) compared to fertile flowers. In addition, an increase in inflorescence mass involved a disproportionate increase in mass allocation to male, rather than female, flowers. This pattern also contrasts with a size-related gender change from male to female in Arisaema species. These findings were consistent with sex allocation model predictions and shed light on the evolution of sex lability in Arisaema species.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Méndez Msubject
Has Abstractpub_date
2001-10-01 00:00:00pages
1781-5issue
10eissn
0002-9122issn
1537-2197pii
88/10/1781journal_volume
88pub_type
杂志文章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
pub_type: 杂志文章
doi:10.3732/ajb.1600345
更新日期:2017-01-01 00:00:00
abstract::Isozymatic data taken from 67 Guatemalan collections of maize were subjected to numerical taxonomic analyses to elucidate systematic relationships among the 19 maize races and subraces described for Guatemala by Wellhausen et al. As with Bolivian and Mexican races, isozymatic variation in Guatemalan maize was strongly...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/j.1537-2197.1990.tb13547.x
更新日期:1990-02-01 00:00:00
abstract::Individual plants of Asclepias exaltata (Asclepiadaceae) typically express an unusual self-incompatibility system under single-gene control. Hand-pollinations performed in six natural populations detected occasional self-fertile plants. The frequency of self-fertile individuals ranged from 0 to 34.0% and differed sign...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-08-01 00:00:00
abstract:PREMISE OF THE STUDY:Although our awareness of ploidy diversity has expanded with the application of flow cytometry, we still know little about the extent to which cytotypes within mixed-ploidy populations are genetically differentiated across environmental gradients. METHODS:To address this issue, we reared 14 popula...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500146
更新日期:2016-01-01 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:UNLABELLED: PREMISE OF THE STUDY:Phenolic compounds exuded by roots have been implicated in allelopathic interactions among plants. Root enzymes that destroy phenolics may protect plants against allelopathic inhibition and thus may aid in invasiveness. Phenolic-degrading enzymes are chiefly found in aboveground plant ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900337
更新日期:2010-07-01 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
pub_type: 杂志文章
doi:10.3732/ajb.1500249
更新日期:2015-10-01 00:00:00
abstract::Hybridization and introgression play important roles in plant evolution, and their occurrence on the oceanic islands provides good examples of plant speciation and diversification. Restriction fragment length polymorphisms (RFLPs) and trnL (UAA) 3'exon-trnF (GAA) intergenic spacer (IGS) sequences of chloroplast DNA (c...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-06-01 00:00:00
abstract:PREMISE OF THE STUDY:Many ecological and evolutionary processes shape the assembly of organisms into local communities from a regional pool of species. We analyzed phylogenetic and functional diversity to understand community assembly of the ferns of Florida at two spatial scales. METHODS:We built a phylogeny for 125 ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1073
更新日期:2018-03-01 00:00:00
abstract::Gaura (Onagraceae: Onagreae) is a small North American genus of 21 species consisting mostly of night-blooming, moth-pollinated annuals and perennials. The current infrageneric classification based on differences in habit, floral symmetry, and fruit morphology recognizes eight sections within the genus. We examine the...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.1.139
更新日期:2004-01-01 00:00:00
abstract::In plants, polyploidy has been a significant evolutionary force on both recent and ancient time scales. In 1950, Ownbey reported two newly formed Tragopogon allopolyploids in the northwestern United States. We have made the first synthetic lines of T. mirus and T. miscellus using T. dubius, T. porrifolius, and T. prat...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800299
更新日期:2009-05-01 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
pub_type: 杂志文章
doi:10.3732/ajb.89.8.1197
更新日期:2002-08-01 00:00:00
abstract:PREMISE OF THE STUDY:Seed cone scales assigned to the genus Schizolepidopsis are widespread in Late Triassic to Cretaceous Eurasian deposits. They have been linked to the conifer family Pinaceae based on associated vegetative remains, but their exact affinities are uncertain. Recently discovered material from the Early...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1300173
更新日期:2013-12-01 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
pub_type: 杂志文章
doi:
更新日期:2001-05-01 00:00:00
abstract::Parsimony, likelihood, and Bayesian analyses of nuclear ITS and plastid trnL-F DNA sequence data are presented for the giant genus Croton (Euphorbiaceae s.s.) and related taxa. Sampling comprises 88 taxa, including 78 of the estimated 1223 species and 29 of the 40 sections previously recognized of Croton. It also incl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.9.1520
更新日期:2005-09-01 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
pub_type: 杂志文章
doi:10.3732/ajb.1600278
更新日期:2017-01-01 00:00:00
abstract::Axillary meristems play a fundamental role in inflorescence architecture. Maize (Zea mays) inflorescences are highly branched panicles because of the production of multiple types of axillary meristems. We used auxin transport inhibitors to show that auxin transport is required for axillary meristem initiation in the m...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.11.1745
更新日期:2007-11-01 00:00:00
abstract::Competition and herbivory are ubiquitous environmental challenges that affect most plants. We examined the influence of phenotypic responses to either competition or herbivory on the subsequent response of the plants to the other factor. The stem-elongation response of Chenopodium album to light competition attenuated...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.1.21
更新日期:2005-01-01 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
pub_type: 杂志文章
doi:10.3732/ajb.1000144
更新日期:2010-10-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellite loci were developed for the endangered species Pityopsis ruthii and will permit genetic and conservation studies of the species. METHODS AND RESULTS:A microsatellite-enriched library was used to develop 12 polymorphic microsatellite loci for P. ruthii. The loci amplified perfect and...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100100
更新日期:2011-12-01 00:00:00
abstract::A spatially explicit, reiterative algorithm (SERA) is presented and used to predict multiple aspects of plant population and community dynamics. Using simple physical principles and empirically derived relationships, SERA provides an analytical venue to test alternative hypotheses about individual functional traits go...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900063
更新日期:2009-08-01 00:00:00
abstract:PREMISE OF THE STUDY:Chloroplast microsatellites were developed in Theobroma cacao to examine the genetic diversity of cacao cultivars in Trinidad and Tobago. METHODS AND RESULTS:Nine polymorphic microsatellites were designed from the chloroplast genomes of two T. cacao accessions. These microsatellites were tested in...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100306
更新日期:2011-12-01 00:00:00
abstract::Phylogenetic analyses of Meliaceae, including representatives of all four currently recognized subfamilies and all but two tribes (32 genera and 35 species, respectively), were carried out using DNA sequence data from three regions: plastid genes rbcL, matK (partial), and nuclear 26S rDNA (partial). Individual and com...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.3.471
更新日期:2003-03-01 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::In an age of rapid global change, it is imperative that we continue to improve our understanding of factors that govern genetic differentiation in plants to inform biologically reasonable predictions for the future and enlighten conservation and restoration practices. In this special issue, we have assembled a set of ...
journal_title:American journal of botany
pub_type:
doi:10.3732/ajb.1500515
更新日期:2016-01-01 00:00:00
abstract::The evolutionary history of maize (Zea mays subsp. mays) is of general interest because of its economic and scientific importance. Here we show that many cellular traits described previously in developing caryopses of maize are also seen in its wild progenitor teosinte (Zea mays subsp. parviglumis). These features, ea...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900059
更新日期:2009-10-01 00:00:00
abstract::During the crown-building phase, the mechanical architecture of the trunk of Aralia spinosa exhibits considerable ontogenetic variation. All trunks were tapered along their length, and taper was dependent on both ramet size and age; older, larger trunks were more tapered than younger, smaller trunks. Trunk specific gr...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-12-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellite primers were developed in the native legume tree Anadenanthera colubrina var. cebil to study the genetic diversity and genetic structure in natural populations in Argentina. METHODS AND RESULTS:Nine microsatellite markers were identified using a genomic library enriched for tandemly...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200078
更新日期:2012-09-01 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::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
pub_type: 杂志文章
doi:10.3732/ajb.92.12.1935
更新日期:2005-12-01 00:00:00