Recovery of Tomato Plants from Ozone Injury

Abstract

Field experiments in open-top chambers were conducted to study the recovery of tomato (Lycopersicon esculentum Mill. cv. New Yorker) plants from ozone (O3) injury. Plants were pot-cultured and exposed for 7 hours per day for 4 days at a vegetative or flowering stage to charcoal-filtered air, 0.06, 0.09, 0.12, 0.18, or 0.24 μl O3/liter. Half of the plants were harvested 2 or 3 days after the O3 exposure; the remaining plants were held in open-top field chambers in filtered air and harvested after the appearance `of the first red fruit. Ozone exposure at either growth stage resulted in visible foliar injury and decreased leaf area of plants harvested 2 or 3 days after exposure. In spite of extensive foliar injury after O3 exposure at the vegetative stage, there was no significant decrease in fruit yield or change in fruit quality at the final harvest. In contrast, exposure of plants to O3 at flowering progressively reduced fresh weight of fruit and, to a lesser degree, its concentration of titratable acidity.