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. Therefore, a data set was designed here to include critical taxa that were not included in earlier studies. More than 5000 bp from the plastid (rbcL, atpB, rps4) and the nuclear (18S rDNA) genomes were sequenced for 62 taxa. Phylogenetic analyses of these data (1) confirm that Osmundaceae are sister to the rest of the leptosporangiates, (2) resolve a diverse set of ferns formerly thought to be a subsequent grade as possibly monophyletic (((Dipteridaceae, Matoniaceae), Gleicheniaceae), Hymenophyllaceae), and (3) place schizaeoid ferns as sister to a large clade of "core leptosporangiates" that includes heterosporous ferns, tree ferns, and polypods. Divergence time estimates for ferns are reported from penalized likelihood analyses of our molecular data, with constraints from a reassessment of the fossil record.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Pryer KM,Schuettpelz E,Wolf PG,Schneider H,Smith AR,Cranfill Rdoi
10.3732/ajb.91.10.1582subject
Has Abstractpub_date
2004-10-01 00:00:00pages
1582-98issue
10eissn
0002-9122issn
1537-2197pii
91/10/1582journal_volume
91pub_type
杂志文章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
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abstract:PREMISE OF THE STUDY:Little is known about the effect of environmental conditions on seed dormancy break at the community level or how it could be affected by climate change. This study tested the effects of storage conditions on germination of 489 species from high-elevation natural grasslands on the Tibet Plateau. M...
journal_title:American journal of botany
pub_type: 杂志文章
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journal_title:American journal of botany
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2016-01-01 00:00:00
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journal_title:American journal of botany
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journal_title:American journal of botany
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:1991-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2004-07-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2001-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2017-06-01 00:00:00
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journal_title:American journal of botany
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journal_title:American journal of botany
pub_type: 杂志文章,评审
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更新日期:2014-09-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2016-11-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1389
更新日期:2019-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.1200359
更新日期:2013-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.94.10.1630
更新日期:2007-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.3732/ajb.91.9.1371
更新日期:2004-09-01 00:00:00
abstract::Floral morphology of the 13 species of Moringa ranges from actinomorphic flowers with little hypanthium to highly zygomorphic flowers with well-developed hypanthia. Scanning electron and light microscopy were used to identify ontogenetic differences among two actinomorphic and eight zygomorphic species. All species sh...
journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2003-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2011-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2002-01-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2005-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2010-02-01 00:00:00
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journal_title:American journal of botany
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更新日期:2017-10-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2002-04-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2007-06-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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更新日期:2002-03-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-11-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
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