Ozone concentration in leaf intercellular air spaces is close to zero
- Institute of Astrophysics and Atmospheric Physics, Tartu, Estonia (USSR)
- Tartu State Univ., Tartu, Estonia (USSR)
Transpiration and ozone uptake rates were measured simultaneously in sunflower leaves at different stomatal openings and various ozone concentrations. Ozone uptake rates were proportional to the ozone concentration up to 1500 nanoliters per liter. The leaf gas phase diffusion resistance (stomatal plus boundary layer) to water vapor was calculated and converted to the resistance to ozone multiplying it by the theoretical ratio of diffusion coefficients for water vapor and ozone in air (1.67). The ozone concentration in intercellular air spaces calculated from the ozone uptake rate and diffusion resistance to ozone scattered around zero. The ozone concentration in intercellular air spaces was measured directly bu supplying ozone to the leaf from one side and measuring the equilibrium concentration above the other side, and it was found to be zero. The total leaf resistance to ozone was proportional to the gas phase resistance to water vapor with a coefficient of 1.68. It is concluded that ozone enters the leaf by diffusion through the stomata, and is rapidly decomposed in cell walls and plasmalemma.
- OSTI ID:
- 6967922
- Journal Information:
- Plant Physiology; (USA), Vol. 90:3; ISSN 0032-0889
- Country of Publication:
- United States
- Language:
- English
Similar Records
Leaf energy balance and transpirational relationships of tulip poplar (Liriodendron tulipifera)
Photosynthesis, transpiration, leaf temperature, and stomatal activity of cotton plants under varying water potentials