Abstract:
:Extreme preformation, the initiation of leaves or inflorescences more than 1 yr before maturation and function, is common in arctic and alpine habitats. This extended pattern of development provides a potential means to alleviate an apparent asynchrony between carbon supplied by photosynthesis in the summer and carbon demanded by growth in the spring. Allocation of resources to preforming organs has not been studied in herbs with multi-year patterns of preformation. Acomastylis rossii (Rosaceae) in the southern Rockies initiates leaves and inflorescences 2 yr prior to their maturation and function. Allocation to preforming organs in A. rossii was studied by means of a labeled carbon pulse chase experiment. During the summer, carbon is allocated directly to preforming organs and rhizomes from the mature leaves. Additional allocation of carbohydrate into preforming organs occurs in autumn after photosynthesis by mature leaves has ceased. Organ primordia initiated in the second year do not receive a substantial quantity of the labeled carbon from reserves stored in the rhizome the previous year. We conclude that concurrent photosynthesis is the primary source of carbon for preformation development.
journal_name
Am J Botjournal_title
American journal of botanyauthors
Meloche CG,Diggle PKdoi
10.3732/ajb.90.9.1313subject
Has Abstractpub_date
2003-09-01 00:00:00pages
1313-20issue
9eissn
0002-9122issn
1537-2197pii
90/9/1313journal_volume
90pub_type
杂志文章abstract::The pattern of DNA, RNA, and protein synthesis during lateral root initiation in Marsilea quadrifolia L. was monitored by autoradiography of incorporated of 3H-thymidine, 3H-uridine, and 3H-leucine, respectively. DNA synthesis was associated with the enlargement of the lateral root initial prior to its division. Con...
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,评审
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更新日期:2014-01-01 00:00:00
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doi:10.3732/ajb.89.11.1741
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更新日期:2006-06-01 00:00:00
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pub_type: 杂志文章
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pub_type: 杂志文章
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更新日期:2012-01-01 00:00:00
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