Effect of Flooding on Ethylene Concentration in Horticultural Plants1

Abstract

Ethylene concentrations in leafless softwood cuttings of Malus robusta and Ligustrum obtusifolium and in leafy cuttings of Chrysanthemum morifolium increased in non-submerged controls steeped upright in water 2.5 cm deep for 20 hr. Increase in ethylene concn was greater in submerged cuttings than in controls. Ethylene concn in fruits of Malus pumila ‘Red Gold’ and ‘Jonathan’ increased during 24 hr submersion. In Lycopersicon esculentum , however, submersion decreased ethylene concn in both young and mature fruits. Ethylene concn in bulbs of Tulipa fosteriana ‘Red Emperor’ increased in those submerged and the control, but with no significant difference between them. In bulbs of Tulipa gesneriana ‘Peach Blossom’ and tubers of Solanum tuberosum ‘Katahdin’, no ethylene gas was detected either before or after submersion. Flooding the bases of intact plants of Chrysanthemum morifolium, Helianthus annuus, Lycopersicon esculentum , and Raphanus sativus for 24 hr increased ethylene concn in submerged stems and roots, while it did not change ethylene concn in controls. When roots and basal stems of Chrysanthemum morifolium and Helianthus annuus plants were flooded, ethylene concn in non-flooded stems adjacent to flooded stems also increased. When the bases of intact Lycopersicon esculentum plants were flooded, ethylene concn was greater in the lower half of the submerged portion than in the upper half.