Porat, R., The Kennedy-Leigh Centre for Horticulture Research, Faculty of Agriculture, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot, 76100, Israel
Borochov, A., The Kennedy-Leigh Centre for Horticulture Research, Faculty of Agriculture, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot, 76100, Israel
Halevy, A.H., The Kennedy-Leigh Centre for Horticulture Research, Faculty of Agriculture, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot, 76100, Israel

Methyl jasmonate (JA-Me), applied to dendrobium and petunia flowers either as an aqueous solution through the cut stem or stigma, or as a gas, accelerated senescence. The rate of appearance of wilting symptoms was directly related to the amount of JA-Me applied to the flowers. JA-Me increased ethylene production by the flowers, irrespective of application method, and this effect was also proportional to the dose of the compound. In both dendrobium and petunia flowers, the JA-Me induced increases in ethylene production and 1-aminocyclopropane-1-carboxylic acid content followed similar patterns. Aminooxyacetic acid, an inhibitor of ACC-synthase, and silver-thiosulfate, an inhibitor of ethylene action, completely inhibited the effects of JA-Me. It is concluded that JA-Me enhances petunia and dendrobium flower senescence via the promotion of ACC and ethylene production. © 1993 Kluwer Academic Publishers.