Sugar and organic acid accumulation in guard cells of Vicia faba in response to red and blue light

Journal Article · Sun Aug 01 00:00:00 EDT 1993 · Plant Physiology; (United States)

OSTI ID:5696145

Talbott, L D; Zeiger, E ^[1]

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1. Univ. of California, Los Angeles, CA (United States)

Changes in neutral sugar and organic acid content of guard cells were quantitated by high-performance liquid chromatography during stomatal opening in different light qualities. Sonicated Vicia faba epidermal peels were irradiated with 10 [mu]mol m[sup [minus]2] s[sup [minus]1] of blue light, a fluence rate insufficient for the activation of guard cell photosynthesis, or 125 [mu]mol m[sup [minus]2] s[sup [minus]1] of red light, in the presence of 1mM KCl, 0.1 mM CaCl[sub 2]. The low-fluence-rate blue light stimulated an average net stomatal opening of 4.7 [mu]m in 2 h, whereas the saturating fluence rate of red light stimulated an average net opening of 3.8 [mu]m in 2 h. Under blue light, the malate content of guard cells increased to 173% of the initial level during the first 30 min of opening and declined as opening continued. Sucrose levels continuously rose throughout the blue light-stimulated opening, reaching 215% of the initial level after 2 h. The starch hydrolysis products maltose and maltotriose remained elevated at all times. Under red light, guard cells showed very little increase in organic acid or maltose levels, whereas sucrose levels increased to 208% of the initial level after 2 h. Total measured organic metabolite concentrations were correlated with stomatal apertures in all cases except where substantial malate increases occurred. These results support the hypothesis that light quality modulates alternative mechanisms of osmotic accumulation guard cells, including potassium uptake, photosynthetic sugar production, and starch breakdown. 29 refs., 5 figs., 2 tab.

• OSTI ID: 5696145
• Journal Information: Plant Physiology; (United States), Vol. 102:4; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
MALTOSE
ECOLOGICAL CONCENTRATION
ORGANIC ACIDS
PLANT CELLS
PHOTOSYNTHESIS
VISIBLE RADIATION
BIOLOGICAL EFFECTS
HYDROLYSIS
PHOTOCHEMICAL REACTIONS
STARCH
STOMATA
VICIA
CARBOHYDRATES
CHEMICAL REACTIONS
DECOMPOSITION
DISACCHARIDES
ELECTROMAGNETIC RADIATION
LEGUMINOSAE
LYSIS
MAGNOLIOPHYTA
MAGNOLIOPSIDA
OLIGOSACCHARIDES
OPENINGS
ORGANIC COMPOUNDS
PLANTS
POLYSACCHARIDES
RADIATIONS
REAGENTS
SACCHARIDES
SOLVOLYSIS
SYNTHESIS
550200* - Biochemistry