Assimilate utilization in the leaf canopy and whole-plant growth of soybean during acclimation to elevated CO/sub 2/

Journal Article · Thu Jan 01 04:00:00 EST 1987 · Bot. Gaz. (Chicago); (United States)

DOI:https://doi.org/10.1086/337628· OSTI ID:6149725

Cure, J D; Rufty, Jr, T W; Israel, D W

Young vegetative soybeans (Glycine max 'Ransom') were exposed to control (350 ..mu..L L/sup /minus/1/ CO/sub 2/) or CO/sub 2/minus// enriched (700 ..mu..L L/sup /minus/1/ CO/sub 2/) environments continuously for 22 days. Alternations in carbon acquisition, assimilate utilization by the leaf canopy, and whole-plant growth were followed to characterize plant acclimation at high CO/sub 2/. Whole-plant dry weight (DW) progressively increased at high CO/sub 2/ relative to the control throughout the experiment. The initial DW increases were associated with the accumulation of nonstructural assimilates in leaves and increased specific leaf weight (SLW). After 3 days, however, DW began to accumulate rapidly in stems and roots under high CO/sub 2/, and SLW no longer increased relative to controls. Total leaf area did not increase significantly at high CO/sub 2/ until 13 days after the start of treatments. Net assimilation rates declined under both CO/sub 2/ conditions but remained higher at 700 ..mu..L L/sup /minus/1/ CO/sub 2/ throughout the experiment. The increases in stem and root DW during week 1 at high CO/sub 2/ were accompanied by (1) an early increase in the estimated rate of assimilate utilization in the canopy during the dark phase of the diurnal cycle and (2) a later increase in the estimated rate of assimilate utilization during the light phase. The results indicate that dark mobilization of assimilates from source leaves responded to variations in assimilate accumulation but that export of assimilates from source leaves in the light adjusted more slowly and appeared to be coordinated with large changes in sink activity in the whole plant. 32 refs., 7 figs.

• Research Organization: Botany Department, Duke University, Durham, North Carolina 27706; USDA-ARS, Oxford, North Carolina 27565 and Raleigh, North Carolina 27695; Department of Crop Science, Botany and Soil Science, North Carolina State University, Raeligh, North Carolina 27695
• OSTI ID: 6149725
• Journal Information: Bot. Gaz. (Chicago); (United States), Journal Name: Bot. Gaz. (Chicago); (United States) Vol. 148:1; ISSN BOGAA
• Country of Publication: United States
• Language: English

Related Subjects

500200* -- Environment
Atmospheric-- Chemicals Monitoring & Transport-- (-1989)
54 ENVIRONMENTAL SCIENCES
553000 -- Agriculture & Food Technology
60 APPLIED LIFE SCIENCES
AMINO ACIDS
BIOMASS
CARBON COMPOUNDS
CARBON DIOXIDE
CARBON OXIDES
CARBOXYLIC ACIDS
CHALCOGENIDES
CHEMICAL REACTIONS
ECOLOGICAL CONCENTRATION
ENERGY SOURCES
EVALUATION
GLYCINE
GROWTH
LEAVES
ORGANIC ACIDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOSYNTHESIS
PLANT GROWTH
RENEWABLE ENERGY SOURCES
SYNTHESIS
VARIATIONS