Light, temperature and nutrients as factors in photosynthetic adjustment to elevated carbon dioxide

Conference · Wed May 01 00:00:00 EDT 1991 · Plant Physiology, Supplement; (United States)

OSTI ID:5598507

Bunce, J; Lee, D ^[1]

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1. Dept. of Agriculture, Beltsville, MD (United States)

It has been noted many times that the short-term stimulation of photosynthesis by elevated carbon dioxide usually observed in C3 plants may not persist in the long-term. Experiments were designed to test the hypotheses that photosynthetic adjustment to elevated carbon dioxide is due to (a) feedback inhibition resulting from excess photosynthate production relative to use, and (b) nutrient deficiency resulting from more rapid growth. Soybeans and sugarbeets were grown in controlled environment chambers at 350 and 700 ppm carbon dioxide, at two temperatures, two levels of photosynthetically active radiation, and with three nutrient regimes in a factorial design. Net carbon dioxide uptake rates of individual leaves from all growth conditions were measured at both 350 and 700 ppm carbon dioxide to assay photosynthetic adjustment to the elevated carbon dioxide. Growth at elevated carbon dioxide reduced rates of photosynthesis measured at standard carbon dioxide levels in both species. Photosynthetic rates measured at 350 ppm were lower on average by 33% in sugarbeet and 23% in soybean after growth at elevated carbon dioxide. Photosynthetic adjustment to elevated carbon dioxide was not greater after growth at 1.0 than 0.5 mmol m{sup {minus}2}s{sup {minus}1} PPFD, was not greater at 20 than 25C growth temperature, and could not be overcome by high rates of nutrient application. These results do not support either the feedback inhibition nor nutrient deficiency hypotheses of photosynthetic adjustment to elevated carbon dioxide. In soybeans, complete photosynthetic adjustment could be induced by a single night at elevated carbon dioxide.

• OSTI ID: 5598507
• Report Number(s): CONF-9107184-; CODEN: PPYSA
• Journal Information: Plant Physiology, Supplement; (United States), Vol. 96:1; Conference: Annual meeting of the American Society of Plant Physiology, Albuquerque, NM (United States), 28 Jul - 1 Aug 1991; ISSN 0079-2241
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
CARBON DIOXIDE
BIOLOGICAL EFFECTS
PLANTS
PHOTOSYNTHESIS
BIOLOGICAL ADAPTATION
EXPOSURE CHAMBERS
GLYCINE HISPIDA
NUTRIENTS
NUTRITIONAL DEFICIENCY
PLANT GROWTH
SUGAR BEETS
TEMPERATURE EFFECTS
UPTAKE
VISIBLE RADIATION
BEETS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
ELECTROMAGNETIC RADIATION
FOOD
GROWTH
LEGUMINOSAE
MAGNOLIOPHYTA
MAGNOLIOPSIDA
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
RADIATIONS
SYNTHESIS
VEGETABLES
560300* - Chemicals Metabolism & Toxicology
551000 - Physiological Systems