Abstract：
:Chrysothamnus nauseosus (Asteraceae) is a complex polymorphic shrub species widely distributed in western North America. In a study of 86 populations belonging to 15 subspecies, achene mass varied among populations over a sevenfold range. Achene mass was closely correlated with capitulum size at the subspecies level, varied little between wild-growing and common-garden-grown members of a population, and was under strong genetic control. Subspecies with the heaviest achenes are restricted to specialized edaphic environments (dunes and badlands) or late seral montane riparian communities, while subspecies that are widely distributed and that occur in early seral habitats have less heavy achenes. Selection on achene mass has apparently been a notable feature of the adaptive radiation of Chrysothamnus nauseosus into the wide array of habitats it currently occupies. Within a wild population, achene mass was greater for plants fruiting in midautumn than for plants fruiting early or late in the autumn, and this same trend was observed within individual plants in garden populations, indicating environmental control, perhaps through resource limitation. Highly significant between-plant differences in achene mass were found in both wild and garden populations, suggesting that within-population genetic variation is sufficient to permit continuing selection.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Meyer Ssubject
Has Abstractpub_date
1997-04-01 00:00:00pages
471issue
4eissn
0002-9122issn
1537-2197pii
84/4/471journal_volume
84pub_type
杂志文章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：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：:The genus Caltha (Ranunculaceae) consists of 10 species of low-growing, perennial herbs distributed throughout the moist temperate and cold regions of both the Northern and Southern Hemispheres. Traditionally, the species have been divided into two sections: section Psychrophila in the Southern Hemisphere with diploph...
journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.2.247
更新日期：2004-02-01 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
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1000300
更新日期：2010-11-01 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
doi：10.3732/ajb.1600339
更新日期：2017-07-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.5.760
更新日期：2004-05-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.91.1.37
更新日期：2004-01-01 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：2016-01-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.0900394
更新日期：2010-03-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/j.1537-2197.1990.tb13579.x
更新日期：1990-04-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400272
更新日期：2014-11-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2000-06-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1100568
更新日期：2012-06-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.92.10.1723
更新日期：2005-10-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-10-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1556
更新日期：2020-11-01 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：2015-03-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：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：2010-01-01 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：2009-09-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-06-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：1999-09-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.93.2.197
更新日期：2006-02-01 00:00:00
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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
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journal_title：American journal of botany
pub_type： 杂志文章
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更新日期：2010-08-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.3732/ajb.1400143
更新日期：2014-10-01 00:00:00
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journal_title：American journal of botany
pub_type： 杂志文章
doi：10.1002/ajb2.1285
更新日期：2019-05-01 00:00:00
abstract：:Gregor Mendel was a 19(th) century priest and botanist who developed the fundamental laws of inheritance. The year 2000 marked a century since the rediscovery of those laws and the beginning of genetics. Although Mendel is now recognized as the founder of genetics, significant controversy ensued about his work through...
journal_title：American journal of botany
pub_type： 杂志文章
doi：
更新日期：2001-05-01 00:00:00
