Abstract: During the development of short catkinsmutant, the upper parts became yellow, curved, and
finally dropped off gradually, while the basal catkins still developed normally. The ultrastructure changes of
cellswere observed during upper naturally degradation by using transmission electron microscope. The results
exhibited orderly changes in death: the nucleus showed chromatin condensation, the nucleolus dissolved, kar
yop lasm degraded, the karyotheca burst and the nucleus disintegrated, the vacuole happened distinct swallow,
and some formed into many small vacuoles, the chlorop last and mitochondrion disintegrated gradually. The
morphological changes during the death of all the organelleswithin the cell showed the typ ical features of p ro
grammed cell death.

Key words: Chestnut, Short catkin, Ultrastructure, Programmed cell death