Sex expression and the production of ethylene induced by auxin in the cucumber (Cucumis sativum L.)

Abstract

Laibach and Kribben1 and others2,3 have reported altering the sex expression of monoecious cucumber plants by applying auxins to growing plants. The treatments increased the ratio of female to male flowers. A considerable change toward femaleness in cucumbers was reported4 as a result of a single treatment with 2-chloroethylphosphonic acid (CEPA), which causes the release of ethylene5. There are reports that the production of ethylene is induced in many plants after treatment with indoleacetic acid (IAA)6,7 or naphthaleneacetic acid (NAA)8. We have evidence that cucumber plants treated with auxins or CEPA also produce ethylene, which, we suggest, alters the sex expression of the treated plants. © 1969 Nature Publishing Group.