Phenotypic Stability and Ethylene Evolution in Androecious Cucumber1

Abstract Effects of 4 daylength and temperature combinations on sex expression and growth of androecious (allmale) cucumber ( Cucumis sativus L.) were studied. Three of 4 androecious lines were stable for male expression under all 4 combinations. However, low temperature and short days promoted femaleness in one line causing monoecious expression. Ethylene production by androecious was compared to that of monoecious, andromonoecious, hermaphroditic and gynoecious phenotypes. Low ethylene evolution was associated with plants of androecious and monoecious phenotypes as compared to more female phenotypes. Furthermore, ethylene production by androecious plants remained low and constant throughout 30 days of growth, but a small peak in ethylene production by monoecious plants was noted. This small peak may be associated with the initiation of female flowers in monoecious phenotypes.