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 (O 3 ) 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 O 3 /liter. Half of the plants were harvested 2 or 3 days after the O 3 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 O 3 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 O 3 at flowering progressively reduced fresh weight of fruit and, to a lesser degree, its concentration of titratable acidity.