Abstract:
:The endodermis of different species of the genus Equisetum has different configurations, two or one continuous layers or a sheath only around the vascular bundles. The question whether the endodermis contributes to the mechanical stability of the aerial shoots is investigated in two ways: In a direct approach, the endodermis of segments of E. hyemale was dissected longitudinally and the mechanical stability against ovalization measured as a function of the orientation of the cuts with respect to the forces applied. A comparative approach tested the mechanical stability of eight different species of Equisetum against ovalization of the cross-section for samples, which were either fully turgescent or had reduced turgor pressure. The double-layer endodermis substantially contributed to the mechanical stability of E. affinis and E. hyemale. Equisetum arvense, E. pratense, E. sylvaticum, and E. telmateja are mechanically stabilized by their single layer of endodermis at least under conditions of low turgor pressure.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Spatz HC,Emanns Adoi
10.3732/ajb.91.11.1936subject
Has Abstractpub_date
2004-11-01 00:00:00pages
1936-8issue
11eissn
0002-9122issn
1537-2197pii
91/11/1936journal_volume
91pub_type
杂志文章abstract::Seed size and germination requirements of eight (of nine) Sarracenia species, and 13 populations of S. purpurea were studied. All species except for S. purpurea are restricted to the southeastern United States, whereas S. purpurea ranges across Canada, southward along the eastern United States into Maryland and Virgin...
journal_title:American journal of botany
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doi:
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
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pub_type: 杂志文章
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更新日期:2015-06-01 00:00:00
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pub_type: 杂志文章
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更新日期:2015-07-01 00:00:00
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pub_type: 杂志文章
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更新日期:2018-03-01 00:00:00
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更新日期:1987-01-01 00:00:00
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更新日期:2011-07-01 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:2015-05-01 00:00:00
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journal_title:American journal of botany
pub_type: 杂志文章
doi:
更新日期:1999-12-01 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
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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
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更新日期:1975-01-01 00:00:00
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journal_title:American journal of botany
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