Evidence for genetic control of response to sulfur dioxide and ozone in Populustremuloides

Abstract

This study was designed to estimate the degree of genetic control of the response to sulfur dioxide (SO2) and ozone (O3), alone and in combination, in trembling aspen (Populustremuloides Michx.). Rooted cuttings from 11 randomly selected trees in central Wisconsin were used in the study. Significant interclonal variation was found in the response of the 11 clones to 3-h exposures to 0.50 ppm SO2, 0.20 ppm O3, and 0.35 ppm SO, plus 0.05 ppm O3. Clonal repeatability estimates of 0.464 for SO2 plus O3, 0.620 for O3, and 0.642 for SO2 suggest that much of this variation between clones can be attributed to genetic differences in response to SO2 and O3.