Foliar Injury and Growth of Tomato Cultivars as Influenced by Ozone Dose and Plant Age1

Abstract

Six cultures of Lycopersicon esculentum Mill. were exposed to 3 doses of ozone (O3) at 3 ages. Cultivars exposed to O3 at 2 weeks age ranked differently in sensitivity based on foliar injury than cultivars exposed at 4 and 6 weeks. Cultivars were more sensitive to O3 at 4 than at 6 weeks but sensitivity rankings based on foliar injury were similar. The highest O3 dose significantly inhibited the growth of all cultivars, except ‘Heinz 1439’ at 6 weeks. Cultivar rankings based on average percent change in growth from control plants were more similar at 4 and 6 weeks compared with 2 weeks.