Abstract：
:Polyploid speciation is an ongoing, important source of angiosperm diversity. However, the barriers to polyploid speciation and mechanisms of establishment remain poorly understood for all but a few species. Several factors likely to have influenced tetraploid establishment, including barriers to triploid formation, consequences of mixed-ploidy pollen loads, and the reproductive success of the minority cytotype, were examined in snow buttercups (Ranunculus adoneus) through a series of pollination and transplant experiments. Tetraploid snow buttercups do not have stigmatic barriers to pollen from diploid plants, nor does pollen from tetraploid plants have an advantage over pollen from diploids when on tetraploid stigmas. Tetraploid plants transplanted into a diploid population produced 50% fewer seeds than tetraploid plants in a tetraploid population. Intrinsic barriers to triploid formation were relatively weak, but few triploid seeds formed when mixed-ploidy pollen was present. Fecundity of triploid plants was very low, and no tetraploid offspring resulted. These results indicate that in snow buttercups, a triploid plant will contribute 0.8% of the tetraploid seeds of a minority tetraploid plant making it a minor contributor to the demographics of tetraploid establishment. The reproductive costs facing minority cytotype plants may explain the previously observed spatial segregation in snow buttercups.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Baack EJdoi
10.3732/ajb.92.11.1827subject
Has Abstractpub_date
2005-11-01 00:00:00pages
1827-35issue
11eissn
0002-9122issn
1537-2197pii
92/11/1827journal_volume
92pub_type
杂志文章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-distanc...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-04-01 00:00:00
abstract：PREMISE OF THE STUDY:The species boundaries of wild and cultivated potatoes are controversial, with most of the taxonomic problems in the cultivated potato clade. We here provide the first in-depth phylogenetic study of the cultivated potato clade to explore possible causes of these problems. METHODS:We examined 131 d...
journal_title：American journal of botany
pub_type： 杂志文章
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更新日期：2018-01-01 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：2016-12-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
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journal_title：American journal of botany
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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：2004-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0800176
更新日期：2009-02-01 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：2016-06-01 00:00:00
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更新日期：1988-01-01 00:00:00
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更新日期：2011-12-01 00:00:00
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doi：10.1002/ajb2.1580
更新日期：2020-12-01 00:00:00
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更新日期：2019-09-01 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：2008-06-01 00:00:00
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journal_title：American journal of botany
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更新日期：1992-10-01 00:00:00
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更新日期：2003-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-05-01 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：2013-03-01 00:00:00
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journal_title：American journal of botany
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更新日期：2007-12-01 00:00:00
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journal_title：American journal of botany
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更新日期：2000-11-01 00:00:00
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更新日期：2015-03-01 00:00:00
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journal_title：American journal of botany
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doi：
更新日期：1997-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-12-01 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：1988-05-01 00:00:00
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journal_title：American journal of botany
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更新日期：2017-12-01 00:00:00
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更新日期：2009-01-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-11-01 00:00:00
