Suppression of Ozone-injury on Tomatoes by Ethylene Diurea in Controlled Environments and in the Field1

Abstract

Abstract The systematic antiozonant ethylene diruea (EDU: N-(2-(2-oxo-l-imidazoUdinyl)-ethyl)-N1-phenyI urea) was evaluated on ‘New Yorker’ tomato (Lycopersicon esculentum Mill.) in controlled-environment chambers and ‘New Yorker’ and ‘Tiny Tim’ tomatoes in the field. Ozone injury on juvenile plants resulting from 25 pphm (VV−1) for 6 hr day−1 for 2 days was reduced in controlled environments by foliar sprays of 0.5 g liter−1 or soil drenches of 0.15 g per plant. Foliar injury symptoms were not evident on plants in the field, but yields of ‘Tiny Tim’ increased 30% on those plants sprayed weekly with 1.0 g liter−1 or on plants drenched at planting with 0.5 g per plant followed by 2 side dressings of 0.25 g per plant.