Ethylene-induced Wilting. The first visual symptom of carnations
treated with ethylene was an "in-rolling" or wilting of the
petal margin as described by Nichols (13). Wilting was first
observed at 6 hr for flowers receiving ethylene at 2 ,ul/1 and at 60
hr for those ventilated with air continuously. The number of
flowers exhibiting wilting increased with the duration of exposure
to ethylene. Nine- or 12-hr treatment with ethylene was
sufficient to cause most of the flowers to wilt in 2 days while less
than a third of the flowers receiving 3- or 6-hr exposure displayed
the wilt symptom in this interval. This demonstrates the
variability with respect to sensitivity to ethylene that exists
within a given population of presumably uniform flowers.