The detached petals were prepared by excising them as close as possible
to the receptacle and placing their cut ends in 5-ml vials. Only
petals from the outermost whorl were used. The petals were kept
in water in the test solution under constant cool-white fluorescent
light (2.5 w m-2) at 20°C and 80o RH.
For experiments in which carnation foliage leaves were used,
the third pair of leaves (counting from the flower bud) from a
stem with an open flower was taken.