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 order. These clades, with the exception of the vanilloids, essentially correspond to currently recognized subfamilies. A distinct subfamily, based upon tribe Vanilleae, is supported for Vanilla and its allies. The general tree topology is, for the most part, congruent with previously published hypotheses of intrafamilial relationships; however, there is no evidence supporting the previously recognized subfamilies Spiranthoideae, Neottioideae, or Vandoideae. Subfamily Spiranthoideae is embedded within a single clade containing members of Orchidoideae and sister to tribe Diurideae. Genera representing tribe Tropideae are placed within the epidendroid clade. Most traditional subtribal units are supported within each clade, but few tribes, as currently circumscribed, are monophyletic. Although powerful in assessing monophyly of clades within the family, in this case rbcL fails to provide strong support for the interrelationships of the subfamilies (i.e., along the spine of the tree). The cladograms presented here should serve as a standard to which future morphological and molecular studies can be compared.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Cameron KM,Chase MW,Whitten WM,Kores PJ,Jarrell DC,Albert VA,Yukawa T,Hills HG,Goldman DHsubject
Has Abstractpub_date
1999-02-01 00:00:00pages
208-24issue
2eissn
0002-9122issn
1537-2197pii
86/2/208journal_volume
86pub_type
杂志文章abstract::Phylogenetic relationships among embryophytes (tracheophytes, mosses, liverworts, and hornworts) were examined using 21 newly generated mitochondrial small-subunit (19S) rDNA sequences. The "core" 19S rDNA contained more phylogenetically informative sites and lower homoplasy than either nuclear 18S or plastid 16S rDNA...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-03-01 00:00:00
abstract:PREMISE OF THE STUDY:The classification of the genus Salix has historically been intrinsically difficult due to its propensity toward plasticity and high variation in diagnostic morphological characters. We investigated leaf epidermal characteristics, focusing on the stomatal apparatus because it may provide critical i...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100019
更新日期:2012-04-01 00:00:00
abstract::Multiply sired fruits provide unambiguous evidence that pollen from two or more donors was deposited on a stigma and successfully fertilized ovules. Such multiple paternity within fruits can have important consequences for both parental and offspring fitness, but little is known about the frequency of multiple paterni...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.5.885
更新日期:2005-05-01 00:00:00
abstract::After 120 yr of burial in moist, well-aerated sand, 23 seeds of Verbascum blattaria and two seeds of a Verbascum sp. germinated and produced normal plants (50% germination for Verbascum). After a 6-wk cold treatment, a single seed of Malva rotundifolia germinated also, producing a normal plant (2% germination). Plants...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.8.1285
更新日期:2002-08-01 00:00:00
abstract::Clarkia (Onagraceae) is a genus of 42 annual species, mostly native to California, that has served as a model for many studies of plant evolutionary biology, particularly morphological, cytological, and genetic divergence; reproductive isolation; and speciation. Section Sympherica is the largest section with eight dip...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.2.284
更新日期:2003-02-01 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:PREMISE OF THE STUDY:Intertidal macroalgae must resist extreme hydrodynamic forces imposed by crashing waves. How does frond flexibility mitigate drag, and how does flexibility affect predictions of drag and dislodgement in the field? METHODS:We characterized flexible reconfiguration of six seaweed species in a recirc...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1100541
更新日期:2012-05-01 00:00:00
abstract::Very little is known regarding how repetitive elements evolve inpolyploid organisms. Here we address this subject by fluorescent insitu hybridization (FISH) of 20 interspersed repetitive elements tometaphase chromosomes of the cotton AD-genome tetraploid Gossypiumhirsutum and its putative A- and D-genome diploid ances...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-10-01 00:00:00
abstract::The hollow stem of Equisetum giganteum owes its mechanical stability to an outer ring of strengthening tissue, which provides stiffness and strength in the longitudinal direction, but also to an inner lining of turgid parenchyma, which lends resistance to local buckling. With a height >2.5 m isolated stems are mechani...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1998-03-01 00:00:00
abstract::We examined the function of floral traits associated with buzz pollination through studies of Rhexia virginica (Melastomataceae) in the Muskoka region of Ontario, Canada. Controlled pollinations demonstrated that the species is self-compatible, but dependent on insects for pollen transfer. Bumble bees made 82 and 90% ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::Up to 22% of plant species are the result of breeding among species-hybridization-directly conflicting with the prediction that hybrids, compared to parental species, are intermediate in character and of low fitness and little consequence. Few studies, however, have compared the fitness of hybrids and parental species...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.95.2.146
更新日期:2008-02-01 00:00:00
abstract::Pinus baileyi from the Paleogene of Idaho was initially related to the bristlecone pine P. longaeva (subgen. Strobus, sect. Parrya, subsect. Balfourianae) from western North America. Unlike the centromucronate condition in P. longaeva, P. baileyi cones have raised umbos that are excentromucronate, i.e., the mucro posi...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.2.197
更新日期:2006-02-01 00:00:00
abstract:PREMISE OF THE STUDY:A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1268
更新日期:2019-04-01 00:00:00
abstract::Understanding the role of mother plants as pollen recipients in shaping mating patterns is essential for understanding the evolution of populations and in particular to predict the consequence of habitat fragmentation. Here, we investigated variation in mating patterns due to maternal phenotypic traits, phenological v...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.11.1650
更新日期:2006-11-01 00:00:00
abstract::Zeuxine gracilis, Zeuxine strateumatica, and Eulophia sinensis are wild orchids with different breeding systems and colonizing abilities. Zeuxine gracilis is an outcrosser with restricted distribution, whereas S. strateumatica is an apomictic colonizer found only in newly available open habitats. Eulophia sinensis is ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2001-12-01 00:00:00
abstract::We examined the effects of size and spatial isolation of fens on the isozyme variability of 17 populations of Swertia perennis. This long-lived perennial is a locally abundant fen specialist in Switzerland, where wetlands have been strongly fragmented. Isozyme variability was comparable to other outcrossing plants (A ...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.5.801
更新日期:2002-05-01 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::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: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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0900165
更新日期:2009-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.0800318
更新日期:2009-03-01 00:00:00
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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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200343
更新日期:2013-01-01 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
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.92.10.1632
更新日期:2005-10-01 00:00:00
abstract::Many foliar pathogens require free water to germinate; therefore, disease pressure should favor plants that are able to repel water. For a suite of 18 sympatric clover species (Trifolium and Medicago, Fabaceae), we evaluated leaf traits affecting leaf wetness and susceptibility to infection by the fungal pathogen Stem...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.90.6.857
更新日期:2003-06-01 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::Maximum parsimony analysis of DNA sequence data from the internal and external transcribed spacer (ITS and ETS) regions of 18S-26S nuclear ribosomal DNA and the 3' trnK intron of chloroplast DNA from over 60 populations of Lasthenia sect. Amphiachaenia yielded a well-supported tree showing that the most common species...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.89.7.1103
更新日期:2002-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.93.10.1433
更新日期:2006-10-01 00:00:00
abstract:UNLABELLED:• PREMISE OF THE STUDY:The question why leaf dimensions vary so much between species has long puzzled ecologists. Presumably, variation arises from selective forces acting on leaf function but which selective forces and which leaf functions? This investigation assesses the consistency of divergence in plant...
journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1400379
更新日期:2015-03-01 00:00:00