Growth, fruiting and ethylene binding of tomato plants in response to chronic ethylene exposure

Abstract

Summary‘Red Robin’ tomato plants were grown in chambers containing 0, 0.01, 0.05 or 0.1 µl l−1 ethylene in the atmosphere. Plants in 0.05 or 0.1 µl l−1 ethylene had epinastic leaves. At 0.01 µl l−1 ethylene, visual symptoms were difficult to detect unless an untreated plant was used as a comparison. Even the smallest tested concentrations of ethylene reduced fruit numbers. Plant height of this dwarf tomato variety was not greatly affected by ethylene exposure. Plants exposed to any concentration of ethylene had almost double the ethylene binding capacity of plants grown in ethylene-free air. When plants growing in air were treated with diazocyclopentadiene, an ethylene binding site inhibitor, shoot fresh weight increased, but plant height did not. Thus, endogenous ethylene plays little to no role in determining plant height in this variety.