Abstract：
:Molecular studies of apomictic plant species often detect more genotypic variation than predicted from their assumed reproductive mode. The two most commonly invoked mechanisms to explain these high levels of variation are recombination, via facultative sexuality, and mutation. The potential for sexual reproduction in the facultative apomict Hieracium pilosella (Asteraceae) was determined at three field sites by artificially pollinating with the closely related, but morphologically distinct, H. aurantiacum. The level of genotypic variation at the three sites was recorded using inter-simple sequence repeats (ISSRs). There was a significant, positive relationship between the measured potential for sexual reproduction and population genotypic variability, indicating that sex has played a role in the structuring of these populations; however, a causal relationship cannot be stated because of the use of regression. We also applied the recently developed method of compatibility analysis. Compatibility analysis can determine, using the occurrence of "character incompatibilities," whether patterns of variation observed in populations are most parsimoniously explained by mutation or recombination. Compatibility analysis also indicated that sexual reproduction had played a role in generating genotypic diversity in these populations. Combining these different types of data may give a greater understanding of the potential for the generation of genotypic diversity in facultative apomictic populations.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Houliston GJ,Chapman HMdoi
10.3732/ajb.91.1.37subject
Has Abstractpub_date
2004-01-01 00:00:00pages
37-44issue
1eissn
0002-9122issn
1537-2197pii
91/1/37journal_volume
91pub_type
杂志文章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：:Yucca glauca is a C(3) evergreen rosette species locally common in the C(4)-dominated grasslands of the central Great Plains. Most congeners of Y. glauca are found in deserts, and Y. glauca's morphological similarities to desert species (steeply angled leaves, evergreen habit) may be critical to its success in grassla...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-02-01 00:00:00
abstract：PREMISE OF THE STUDY:We developed microsatellite loci for the biomass crop Miscanthus sinensis to investigate genetic diversity and population structure of M. sinensis and its closely related species. METHODS AND RESULTS:Fourteen microsatellite loci were identified from an enriched genomic library of M. sinensis and t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1100040
更新日期：2011-07-01 00:00:00
abstract：:Seeds are useful in distinguishing among extant genera of Vitaceae and provide a good basis for interpretation of fossil remains in reconstructing the evolutionary and phytogeographic history of this putatively basal Rosid family. Seeds of Ampelocissus s.l. including Pterisanthes and Nothocissus are distinguished from...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.94.9.1534
更新日期：2007-09-01 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
pub_type： 杂志文章
doi：10.3732/ajb.1400234
更新日期：2015-01-01 00:00:00
abstract：:Seventy-four nucleotide sequences from the ITS regions of nuclear ribosomal DNA and 76 from the trnL-trnF spacer of chloroplast DNA were used to address the origin of tetraploid Cardamine amporitana, the conspecifity of central Italian and northeastern Spanish populations, and the possible cause for such geographic di...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.8.1231
更新日期：2004-08-01 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
pub_type： 杂志文章
doi：
更新日期：2000-11-01 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
pub_type： 杂志文章
doi：10.3732/ajb.1700057
更新日期：2017-05-01 00:00:00
abstract：:We sequenced the nuclear small subunit ribosomal DNA coding region from 20 members of the Bangiophycidae and from two members of the Florideophycidae to gain insights into red algal evolution. A combined alignment of nuclear and plastid small subunit rDNA and a data set of Rubisco protein sequences were also studied t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-08-01 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：:The response of axillary buds to floral stimulus activity in stem pieces was examined in two near-isogenic cultivars of tobacco that differ in the recessive maryland mammoth (mm) allele, which confers short-day behavior. All axillary buds from day-neutral plants assayed on six-internode stem pieces made few nodes (les...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
abstract：PREMISE OF THE STUDY:The ability of insect visitors to learn to manipulate complex flowers has important consequences for foraging efficiency and plant fitness. We investigated learning by two butterfly species, Danaus erippus and Heliconius erato, as they foraged on the complex flowers of Asclepias curassavica, as wel...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1700040
更新日期：2017-08-01 00:00:00
abstract：UNLABELLED:• PREMISE OF THE STUDY:Floral traits play important roles in pollinator attraction and defense against floral herbivory. However, plants may experience trade-offs between conspicuousness to pollinators and herbivore attraction. Comparative studies provide an excellent framework to examine the role of multip...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400171
更新日期：2014-08-01 00:00:00
abstract：:Chrysothamnus nauseosus (Asteraceae) is a complex polymorphic shrub species widely distributed in western North America. In a study of 86 populations belonging to 15 subspecies, achene mass varied among populations over a sevenfold range. Achene mass was closely correlated with capitulum size at the subspecies level, ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1997-04-01 00:00:00
abstract：:Although theory has demonstrated rather low levels of gene flow are sufficient to counteract opposing mutation, drift, and selection, widespread recognition of the evolutionary importance of gene flow has come slowly. The perceived role of gene flow as an evolutionary force has vacillated over the last century. In the...
journal_title：American journal of botany
pub_type： 杂志文章,评审
doi：10.3732/ajb.1400024
更新日期：2014-05-01 00:00:00
abstract：:Fitness of interspecific hybrids is sometimes high relative to their parents, despite the conventional belief that they are mostly unfit. F(1) hybrids between oilseed rape (Brassica napus) and weedy B. rapa can be significantly more fit than their weedy parents under some conditions; however, under other conditions th...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.90.4.571
更新日期：2003-04-01 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:Uplift of the tropical Andes had a significant impact on the diversification of South American flora and fauna. Recent biogeographic inquiries have established patterns of Andean divergence, but investigations on ferns are scant. The fern genus Polystichum Roth (Dryopteridaceae) combines widespread...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1300191
更新日期：2014-02-01 00:00:00
abstract：:We assessed the effects of local environment on survival, growth, and development in six clones (genotypes) of Vallisneria americana grown at five sites in the Huron-Erie Corridor. Detrimental effects of local environment on plant performance (rate of clonal growth, leaf and root production, surface area of leaves and...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1997-12-01 00:00:00
abstract：:Many plant species contain populations with more than one polyploid cytotype, but little is known of the mechanisms maintaining several cytotypes in a population. Andropogon gerardii cytotypes were compared to evaluate different models of autopolyploid cytotype coexistence. The enneaploid (90 chromosome, 9x) cytotype ...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-07-01 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：:New individuals in clonal populations arise through the recruitment of sexual or clonal offspring. The predominance of one type of regeneration over the other has been correlated with different selective environmental pressures. We compared the reproductive mode (sexual through seeds and vegetative through plantlets o...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.93.4.505
更新日期：2006-04-01 00:00:00
abstract：PREMISE OF THE STUDY:Herbivory can affect a plant's fitness in a variety of ways, including modifying the biotic interactions of the plant. In particular, when herbivory influences floral display, we hypothesize that pollinator visitation will be altered accordingly. Here we studied the indirect effects of feeding by t...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1500043
更新日期：2015-05-01 00:00:00
abstract：:Sequence data from the intron and spacer of the trnL-F chloroplast region elucidate the phylogenetic relationships of the tribe Diseae (Orchidoideae: Orchidaceae). Within Diseae, 41 species of Disa, two of Brownleea, three of Satyrium, and two of Corycium were included, with five species of Habenaria sensu lato (Orchi...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-11-01 00:00:00
abstract：:Restriction fragment length polymorphism (RFLP) analysis of chloroplast (cp) DNA is a powerful tool for the study of microevolutionary processes in land plants, yet has not previously been applied to seaweed populations. We used cpDNA-RFLP, detected on Southern blots using labeled total plastid DNA, to search for intr...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-07-01 00:00:00
abstract：:Microelectrodes were used to study the oxygen concentration within Myrica gale L. nodules. Low oxygen concentrations were found only in the region of the mature, nitrogen-fixing endophyte, and appeared to correspond to clusters of infected host cells. The oxygen concentration in the remainder of the nodule was much hi...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/j.1537-2197.1983.tb12432.x
更新日期：1983-01-01 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：: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
pub_type： 杂志文章
doi：10.3732/ajb.2007342
更新日期：2008-06-01 00:00:00
abstract：:The effect of microgravity on cellulose synthesis using the model system of Acetobacter xylinum was the subject of recent investigations using The National Aeronautics and Space Administration's Reduced Gravity Laboratory, a modified KC-135 aircraft designed to produce 20 sec of microgravity during the top of a parabo...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1992-11-01 00:00:00
abstract：PREMISE OF THE STUDY:The opuntias (nopales, prickly pears) are not only culturally, ecologically, economically, and medicinally important, but are renowned for their taxonomic difficulty due to interspecific hybridization, polyploidy, and morphological variability. Evolutionary relationships in these stem succulents ha...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1100375
更新日期：2012-05-01 00:00:00
