Sorption of O 3, SO 2, NO 2 or their mixture by nine Poa pratensis cultivars of differing pollutant sensitivity

Abstract

Plants of nine Kentucky bluegrass ( Poa pratensis L.) cultivars were exposed to O 3, SO 2, NO 2 or a mixture of the three gases for three days to determine absorption and adsorption rates of each gas. Absorption rates into stomates differed among cultivars and generally decreased with longer exposure. Leaves of insensitive cultivars generally absorbed less of the single gases than those of sensitive cultivars. There was less absorption of each gas from the mixture than from the single gases. Adsorption rates on leaf surfaces were not always related to cultivar sensitivity and generally decreased less than did adsorption rates with longer exposure. Adsorption rates of O 3 were higher from the single than from mixed gas exposure and of SO 2 were similar from either single or mixed exposure, while the higher rate of NO 2 adsorption, whether from single or mixed gases, varied with cultivar.