Abstract:
:Several alpine species have outlying populations in the lowlands and lower mountains north of the Alps. These small, isolated populations are usually described as either (1) glacial relics, (2) descendants from populations living on forelands and moraines during the ice ages, or (3) populations founded by long-distance dispersal after glaciation. A floristic survey of the historic and present distributions and an allozyme investigation were performed on one of these relic species, Saxifraga aizoides. The species was historically more abundant and had more stations in more regions of northeastern Switzerland. The former population structures within regions, nowadays destroyed, were still reflected in distinct and high regional genetic diversity and variation. There was weak evidence of increased inbreeding in outlying populations, but populations did not deviate from Hardy-Weinberg equilibrium. No geographic pattern of genetic variation above the regional scale (>10 km) was found. Based on the spatial and genetic structures found, it was not possible to discriminate between the abovementioned hypotheses. Nevertheless, the study shows how a thorough evaluation of distribution and abundance data aids the interpretation of genetic data with respect to population history, biogeography, and conservation biology.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Lutz E,Schneller JJ,Holderegger Rsubject
Has Abstractpub_date
2000-04-01 00:00:00pages
583-90issue
4eissn
0002-9122issn
1537-2197pii
87/4/583journal_volume
87pub_type
杂志文章abstract:PREMISE OF THE STUDY:Large genera provide remarkable opportunities to investigate patterns of morphological evolution and historical biogeography in plants. A molecular phylogeny of the species-rich and morphologically and ecologically diverse genus Mimosa was generated to evaluate its infrageneric classification, reco...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1000520
更新日期:2011-07-01 00:00:00
abstract:PREMISE OF THE STUDY:Phenological mismatch has received attention in plant-pollinator interactions, but less so in seed dispersal mutualisms. We investigated whether the seasonal availability of myrmecochorous seeds is well matched to the seasonal activity patterns of seed-dispersing ants. METHODS:We compared seasonal...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1214
更新日期:2019-01-01 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: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::The timing, geographical locations, causes, and consequences of crop domestication have long been major concerns of archaeologists, and agricultural origins and dispersals are currently more relevant than ever to scientists seeking solutions to elusive problems involving food insecurity and global health disparities. ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400145
更新日期:2014-10-01 00:00:00
abstract:PREMISE OF THE STUDY:Global change in temperature and soil nitrogen availability could affect plant community composition, potentially giving an advantage to invasive species compared to native species. We addressed how high temperatures affected CO2 assimilation parameters for invasive Phalaris arundinacea and a sedge...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600339
更新日期:2017-07-01 00:00:00
abstract:PREMISE OF THE STUDY:Microsatellite markers were developed for the dove tree, Davidia involucrata (Cornaceae), a Tertiary relict currently endemic to China, to investigate its population genetics and phylogeography. METHODS AND RESULTS:Using the Fast Isolation by AFLP of Sequences Containing repeats (FIASCO) protocol,...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100414
更新日期:2012-03-01 00:00:00
abstract:PREMISE OF THE STUDY:Drosera peltata var. nipponica, an element of the East Asia warm-temperate vegetation, and D. rotundifolia, a widely distributed boreal species, reach one of their northernmost and southernmost limits, respectively, on the Korean Peninsula. Because the Last Glacial Maximum (LGM)-Holocene dynamics o...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200486
更新日期:2013-11-01 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::The American chestnut (Castanea dentata; Fagaceae) was a dominant canopy tree in the Appalachian Mountains of North America. Since the introduction of the chestnut blight fungus (Cryphonectria parasitica; Valsaceae) in America, the American chestnut has been reduced to a predominantly clonal, understory species. Our o...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.2.207
更新日期:2003-02-01 00:00:00
abstract::Seed size and germination requirements of eight (of nine) Sarracenia species, and 13 populations of S. purpurea were studied. All species except for S. purpurea are restricted to the southeastern United States, whereas S. purpurea ranges across Canada, southward along the eastern United States into Maryland and Virgin...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-03-01 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::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::Recent surveys of seed coat morphology in Lobelioideae (Campanulaceae) have demonstrated the systematic utility of such data in the subfamily and led to a revision of the supraspecific classification of Lobelia. Expanding upon these studies, we examined via scanning electron microscopy 41 seed accessions, emphasizing ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-07-01 00:00:00
abstract::Paniculate agaves from tropical deserts depend on nectar-feeding bats for their reproduction, while species from extratropical areas near the northern limit of Leptonycteris curasoae are pollinated by diurnal and nocturnal insects and birds. Agave angustifolia is a paniculate agave with a broad distribution in Mexico ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.7.1016
更新日期:2003-07-01 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
pub_type: 杂志文章
doi:10.3732/ajb.0900103
更新日期:2010-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Productivity in drylands may depend on the sensitivity of interactions between plants and biocrusts. Given future climate variability, it is essential to understand how interactions may be context-dependent with precipitation regime. Furthermore, little is known about the additional interactions of...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1120
更新日期:2018-07-01 00:00:00
abstract::Woody stems comprise a large biological carbon fraction and determine water transport between roots and leaves; their structure and function can influence both carbon and hydrological cycles. While angiosperm wood anatomy and density determine hydraulic conductivity and mechanical strength, little is known about inter...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900178
更新日期:2010-02-01 00:00:00
abstract:PREMISE:Inbreeding depression is traditionally considered a major factor favoring outcrossing in hermaphrodites. Recent experiments have shown that environmental conditions can influence the magnitude of inbreeding depression, but their relevance in natural populations is unclear. To investigate this, we studied the cl...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1410
更新日期:2020-01-01 00:00:00
abstract::Cladistic parsimony analyses of rbcL nucleotide sequence data from 171 taxa representing nearly all tribes and subtribes of Orchidaceae are presented here. These analyses divide the family into five primary monophyletic clades: apostasioid, cypripedioid, vanilloid, orchidoid, and epidendroid orchids, arranged in that ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-02-01 00:00:00
abstract:PREMISE OF THE STUDY:Despite being highly fertile and occupying a large geographic region, the North American heartleaf bittercress (Cardamine cordifolia; Brassicaceae) has a puzzling triploid-like chromosome number (2n = 3x = 24). As most triploids are sterile, we embarked on a detailed analysis of the C. cordifolia g...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500452
更新日期:2016-07-01 00:00:00
abstract:PREMISE OF THE STUDY:Subtribe Hakeinae (526 spp.) represents a large Australian plant radiation central to our understanding of that flora's evolution and ecology. It contains Grevillea-the third largest plant genus in Australia and a group inferred to have among the highest diversification rates in the angiosperms. Ho...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1500195
更新日期:2015-10-01 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
pub_type: 杂志文章
doi:10.1002/ajb2.1356
更新日期:2019-10-01 00:00:00
abstract:PREMISE OF STUDY:Sequence analyses for Pinaceae have suggested that extant genera diverged in the late Mesozoic. While the fossil record indicates that Pinaceae was highly diverse during the Cretaceous, there are few records of living genera. This description of an anatomically preserved seed cone extends the fossil re...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100568
更新日期:2012-06-01 00:00:00
abstract::Multicellularity has evolved at least once in every major eukaryotic clade (in all ploidy levels) and numerous times among the prokaryotes. According to a standard multilevel selection (MLS) model, in each case, the evolution of multicellularity required the acquisition of cell-cell adhesion, communication, cooperatio...
journal_title:American journal of botany
pub_type: 杂志文章,评审
doi:10.3732/ajb.1300314
更新日期:2014-01-01 00:00:00
abstract:PREMISE OF THE STUDY:Self-incompatibility (SI) is a mechanism that prevents inbreeding in many plant species. The mutational breakdown of SI occurs frequently, yet relatively little is known about the evolutionary steps involved in the progressive loss of pistil and pollen SI function. METHODS:In Solanaceae, SI is the...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1600208
更新日期:2016-10-01 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
pub_type: 杂志文章
doi:10.1002/ajb2.1186
更新日期:2018-11-01 00:00:00
abstract::The direct and indirect effects of vegetative herbivory on the mating system of Impatiens capensis were analyzed through a survey of herbivory in natural I. capensis populations and manipulation of leaf damage in the field. Across 10 wild populations of I. capensis proportion of cleistogamous flowers had a significant...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.7.1046
更新日期:2004-07-01 00:00:00
abstract:UNLABELLED: PREMISE OF THE STUDY:Most studies on orchid hybrids examine separately the effects of hybridization on interactions with pollinators or with mycorrhizal fungi. Here, we simultaneously investigated both interactions in the mediterranean food-deceptive Orchis simia, O. anthropophora, and their hybrid (O. ×be...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900303
更新日期:2010-08-01 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
pub_type: 杂志文章
doi:10.3732/ajb.2007283
更新日期:2008-05-01 00:00:00