Photosynthate partitioning in basal zones of tall fescue leaf blades. [Festuca arundinacea Schreb]

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Plant Physiology; (United States)

DOI:https://doi.org/10.1104/pp.95.3.663· OSTI ID:6098707

Allard, G; Nelson, C J ^[1]

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1. Univ. of Missouri, Columbia (United States)

Elongating grass leaves have successive zones of cell division, cell elongation, and cell maturation in the basal portion of the blade and are a strong sink for photosynthate. Our objective was to determine dry matter (DM) deposition and partitioning in basal zones of elongating tall fescue (Festuca arundinacea Schreb.) leaf blades. Vegetative tall fescue plants were grown in continuous light (350 micromoles per square meter per second photosynthetic photon flux density) to obtain a constant spatial distribution of elongation growth with time. Content and net deposition rates of water-soluble carbohydrates (WSC) and DM along elongating leaf blades were determined. These data were compared with accumulation of {sup 14}C in the basal zones following leaf-labeling with {sup 14}CO{sub 2}. Net deposition of DM was highest in the active cell elongation zone, due mainly to deposition of WSC. The maturation zone, just distal to the elongation zone, accounted for 22% of total net deposition of DM in elongating leaves. However, the spatial profile of {sup 14}C accumulation suggested that the elongation zone and the maturation zone were sinks of equal strength. WSC-free DM accounted for 55% of the total net DM deposition in elongating leaf blades, but only 10% of incoming {sup 14}C-photosynthate accumulated in the water-insoluble fraction (WIF {approximately} WSC-free DM) after 2 hours. In the maturation zone, more WSC was used for synthesis of WSC-free DM than was imported as recent photosynthate.

• OSTI ID: 6098707
• Journal Information: Plant Physiology; (United States), Journal Name: Plant Physiology; (United States) Journal Issue: 3 Vol. 95:3; ISSN 0032-0889; ISSN PLPHA
• Country of Publication: United States
• Language: English

Related Subjects

551001* -- Physiological Systems-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
CARBON 14 COMPOUNDS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
GRAMINEAE
GROWTH
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LEAVES
LILIOPSIDA
MAGNOLIOPHYTA
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PHYSIOLOGY
PLANT GROWTH
PLANTS
SYNTHESIS
TRACER TECHNIQUES