Effect of antagonists of ethylene action on binding of ethylene in cut carnations

Five hours after cut carnations had been treated with a pulse of 1 or 4 mM silver thiosulfate (STS), in vivo ethylene binding in petals was inhibited by 22 and 29%, respectively. When binding was measured 4 days after the 4-mM STS treatment, binding was inhibited by 81%. 2,5-Norbornadiene, which substantially delays carnation senescence, inhibited ethylene binding by 41% at a concentration of 1000 l/l. The Kd for ethylene binding in carnations was estimated to be 0.1 l/l in petals and 0.09 l/l in leaves. The concentration of binding sites was estimated to be 6.0×10^–9 mol/kg of petals and 2.0×10^–9 mol/kg of leaves