Linked Life Data

16662916

Source:http://linkedlifedata.com/resource/pubmed/id/16662916

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2010-6-29
pubmed:abstractText
Exchanges of CO(2) and changes in content of C and N were studied over the life of a leaf of Lupinus albus L. These data were combined with measurements of C:N weight ratios of xylem (upper stem tracheal) and phloem (petiole) sap to determine net fluxes of C and N between leaf and plant. Phase 1 of leaf development (first 11 days, leaf to one-third area) showed increasing net import of C and N, with phloem contributing 61% of the imported C and 18% of the N. (14)C feeding studies suggested the potential for simultaneous import and export through phloem over the period 9 to 12 days. Phase 2 (11-20 days, leaf attaining maximum area and net photosynthesis rate) exhibited net import through xylem and increasing export through phloem. Eighty-two% of xylem-delivered N was consumed in leaf growth, the remainder exported in phloem. Phase 3 (20-38 days) showed high but declining rates of photosynthesis, translocation, and net export of N. Phase 4 (38-66 days) exhibited substantial losses of N and declining photosynthesis and translocation of C. C:N ratio of xylem sap remained constant (2.3-2.6) during leaf life; petiole phloem sap C:N ratio varied from 25 to 135 over leaf development. The relationships between net photosynthesis and N import in xylem were: phase 1, 4.8 milligrams C per milligram N; phase 2, 24.7 milligrams C per milligram N; phase 3, 91.9 milligrams C per milligram N; and phase 4, 47.7 milligrams C per milligram N.
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
Apr
pubmed:issn
0032-0889
pubmed:author
pubmed:issnType
Print
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
835-40
pubmed:dateRevised
2010-9-14
pubmed:year
1983
pubmed:articleTitle
Xylem and Phloem transport and the functional economy of carbon and nitrogen of a legume leaf.
pubmed:affiliation
Department of Botany, University of Western Australia, Nedlands, W. A. 6009, Australia.
pubmed:publicationType
Journal Article