carnation flowers by measuring ethylene production and observing
the change in senescence profiles of the flowers. Figure 1 shows
the changes in ethylene production of the individual flower that senesced naturally, i.e., without pollination. Ethylene production
started on day8, reached a maximum of 1.64 nmol g-1 h-1 on day9,
and slightly declined to1.46 nmol g-1 h-1 on day10, then markedly
declined. It is well known that the maximum ethylene production
is detected just before or at the onset of in-rolling of petals in
naturally-senescing carnation flowers. Actually, the flowers
began to show the in-rolling of petals on day 9 and wilted
completely on day 10-11. Thus the vase life of the flowers was
about 10 days in this experiment. Previously Nukui et al. (2004)
reported that the vase life of ‘LPB’ flowers varied with the flower
samples harvested at different seasons, and the vase life of the
flowers harvested in winter season (December – March) tended
to be longer than that of those harvested in summer season (late
May – September). Regardless of the difference in the time of
harvest, however, ‘LPB’ flowers always produced ethylene in a
climacteric manner and in similar amounts during natural
senescence. In the present investigation, we observed the
variation in the time of maximum ethylene production (varied
from 5 to 9 days) and the length of vase life (varied from 6 to 10
days) in three separate experiments.