Inheritance of Ozone Resistance in Tall Fescue¹

Abstract

Ozone is considered the most important air pollutant affecting vegetation. With progessive urbanization, ozone levels have steadily escalated. Reports suggest that ozone tolerance is a highly heritable characteristic and that the selection of resistant plants and breeding for ozone resistance should be possible. This study was undertaken to gain information on the inheritance of ozone resistance in tall fescue ( Festuca arundinacea Schreb.). Progenies from a diallel among six tall fescue genotypes of diverse origin were evaluated for ozone resistance in a fumigation‐chamber. Sixteen‐day‐old seedlings were exposed to 0.5 ppm ozone for 3 hours and scored for injury after 3 days. General combining ability (GCA) and reciprocal effects were both highly significant; however, GCA constituted a major portion of the genotypic variation. Specific combining ability was not significant. The predominance of additive genetic variance observed indicates that breeding for ozone resistance in this tall fescue population should be possible.