Abstract：
:Breakdown of genetically enforced self-incompatibility (SI), an extremely common and important evolutionary transition in plants, has conventionally been conceived as a qualitative rather than a quantitative change. We evaluated qualitative and quantitative variation in SI for four populations of Witheringia solanacea in Costa Rica, examining growth of self-pollen tubes in pollinations of buds and mature flowers. We also measured levels of RNase production in styles to determine whether enzyme production was correlated with differences in self-rejection. The two small populations contained both self-compatible (SC) individuals and obligate outcrossers (female or SI). Plants in the two large populations were uniformly SI as revealed by pollen tube growth, although several of these individuals sporadically set seed autogamously. Stylar RNase activity did not differ significantly between bud and mature flowers, but self-pollen tube growth did differ, suggesting that a gene product in addition to S-RNase is responsible for developmental onset of SI. Population-level differences in RNase activity were consistent with differences in the strength of the rejection response in bud pollinations, suggesting that a threshold level of S-RNase, in combination with other factors, is necessary for SI. Our results support a growing body of evidence that not only qualitative variation in SI, but also quantitative variation may be functionally significant.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Stone JL,Sasuclark MA,Blomberg CPdoi
10.3732/ajb.93.4.592subject
Has Abstractpub_date
2006-04-01 00:00:00pages
592-8issue
4eissn
0002-9122issn
1537-2197pii
93/4/592journal_volume
93pub_type
杂志文章abstract：:Nuclear DNA contents (4C) were estimated by Feulgen microdensitometry in 27 species of slipper orchids. These data and recent information concerning the molecular systematics of Cypripedioideae allow an interesting re-evaluation of karyotype and genome size variation among slipper orchids in a phylogenetic context. DN...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-05-01 00:00:00
abstract：PREMISE OF THE STUDY:Permineralization provides the most faithful known mode of three-dimensional preservation of the morphology and cellular anatomy of fossil plants. Standard optical microscopic documentation of such structures can provide only an approximation of their true three-dimensional form and is incapable of...
journal_title：American journal of botany
pub_type： 杂志文章
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更新日期：2013-08-01 00:00:00
abstract：UNLABELLED: PREMISE OF THE STUDY:Microsatellite markers were developed in an alpine plant endemic to the Qinghai-Tibetan Plateau, Androsace tapete, to investigate its spatial genetic structure, gene flow, and mating patterns. • METHODS AND RESULTS:Using the combined biotin capture method, 16 microsatellite primer set...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1000260
更新日期：2010-10-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-06-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
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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：1998-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
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更新日期：2006-09-01 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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更新日期：2013-03-01 00:00:00
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pub_type： 杂志文章
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更新日期：2020-08-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1998-06-01 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：2003-10-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1997-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
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更新日期：2003-05-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0800392
更新日期：2009-10-01 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：2008-10-01 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：2014-12-01 00:00:00
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journal_title：American journal of botany
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doi：
更新日期：1997-05-01 00:00:00
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更新日期：2011-08-01 00:00:00
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journal_title：American journal of botany
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doi：
更新日期：2000-07-01 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
doi：
更新日期：2000-12-01 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：2000-09-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1997-07-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
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更新日期：2006-09-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-08-01 00:00:00
