Influence of Air Pollutant Gases on Oxygen Uptake of Pine Roots with Selected Ectomycorrhizae

Abstract

O2 uptake was determined for root segments of greenhouse-grown loblolly pine [Pinus taeda] seedlings, with and without ectomycorrhizae, following exposure to 50 and 500 .mu./m3 O3 or SO2. O2 uptake was determined at 30-min intervals over a 3 h period following a 1 h exposure to each concentration of each gas. The root segments without ectomycorrhizae showed less O2 uptake than those with ectomycorrhizae. Development of ectomycorrhizal-root associations may afford some level of protection for the feeder-root system of loblolly pine trees when exposed to the concentrations of O3 or SO2 common in many areas subject to air pollution.