Abstract:
PREMISE:Variation in seedling emergence timing is considered adaptive over the long term in wild populations, but early emergence can result in a fitness advantage. To explore the adaptive significance of seedling emergence timing, it should be studied under realistic conditions and in the context of other traits that influence fitness. METHODS:In a common garden, we monitored maternal families from seed to flowering (including over winter) with intra- and interspecific competition. We assessed the effects of emergence timing and plant size on survival to anthesis in different genetic backgrounds and under varying competition. KEY RESULTS:We found genetic variation for emergence (probability and timing), size, and survival to anthesis. We also found negative selection, both phenotypic and genetic, on emergence time, such that early emergers (day 8) had almost twice as great a predicted probability of surviving as later emergers (day 28). Size had strong positive effects on survival and, furthermore, the beneficial effects of early emergence may be mediated through size. Maternal family and competitive environment can also affect selection on emergence timing. CONCLUSIONS:Our results indicate that early emergence is related to greater survival in wild sunflower, although there may be little direct selection on this trait; rather, its importance may be mediated by its effects on highly adaptive traits associated with size. Also, the effects of early emergence may vary across genetic backgrounds and competitive conditions, facilitating the maintenance of variation for this trait across a diverse landscape.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Mercer KL,Alexander HM,Snow AAdoi
10.3732/ajb.1000408subject
Has Abstractpub_date
2011-06-01 00:00:00pages
975-85issue
6eissn
0002-9122issn
1537-2197pii
ajb.1000408journal_volume
98pub_type
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journal_title:American journal of botany
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更新日期:2018-05-01 00:00:00
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journal_title:American journal of botany
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doi:10.3732/ajb.90.6.857
更新日期:2003-06-01 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
pub_type: 杂志文章,评审
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更新日期:2012-02-01 00:00:00
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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
doi:
更新日期:2001-09-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1997-05-01 00:00:00
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pub_type: 杂志文章
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更新日期:2012-04-01 00:00:00
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pub_type: 杂志文章
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更新日期:2010-02-01 00:00:00
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更新日期:2002-05-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:2000-12-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:10.1002/ajb2.1478
更新日期:2020-06-01 00:00:00
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journal_title:American journal of botany
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更新日期:1999-11-01 00:00:00
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pub_type: 杂志文章
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更新日期:2005-03-01 00:00:00
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pub_type: 杂志文章
doi:10.3732/ajb.1000469
更新日期:2011-05-01 00:00:00