Metabolic mechanisms of plant growth at low water potentials: Final report

Technical Report · Thu Jan 01 00:00:00 EST 1987

OSTI ID:6896724

Boyer, J S

As proposed, we investigated the effects of low water potentials on cell enlargement and photosynthesis. We described a new instrument (a guillotine psychometer) and method for investigating the control of cell enlargement in plants. The method allows all the factors affecting cell enlargement to be evaluated in a single plant sample growing at a steady rate. All the measurements were conducted while the plants were completely intact with the exception of the yield threshold turgor. This parameter was measured within 5-10 min after excision of the enlarging tissue. Because the time is short, the data probably represented the condition in the intact plant just prior to excision. We investigated the effect of leaf magnesium on the photosynthetic response to low water potential because biochemical work from our laboratory indicated that magnesium concentrations slightly above those normally occurring in the chloroplast stroma resulted in an inhibition of photophosphorylation. The inhibition of photophosphorylation by Mg/sup 2 +/ was similar to that caused by low water potential is that the ATPase activity of coupling factor (the terminal enzyme for phosphorylation in chloroplasts) was inhibited, the conformation of the purified coupling factor protein was altered, and the changes persisted in vitro. 21 refs.

• Research Organization: Texas A and M Univ., College Station (USA). Research Foundation
• DOE Contract Number: FG05-84ER13273
• OSTI ID: 6896724
• Report Number(s): DOE/ER/13273-4; ON: DE88015784
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
09 BIOMASS FUELS
60 APPLIED LIFE SCIENCES
BIOLOGICAL STRESS
GLYCINE HISPIDA
PLANT GROWTH
PLANT CELLS
ULTRASTRUCTURAL CHANGES
METABOLISM
PHOTOSYNTHESIS
PROGRESS REPORT
BACTERIA
CHEMICAL REACTIONS
DOCUMENT TYPES
GROWTH
LEGUMINOSAE
MICROORGANISMS
MORPHOLOGICAL CHANGES
PHOTOCHEMICAL REACTIONS
PLANTS
RHIZOBIUM
SYNTHESIS
551000* - Physiological Systems
140504 - Solar Energy Conversion- Biomass Production & Conversion- (-1989)
553000 - Agriculture & Food Technology