Abstract: Changes in ultra-structure of starch granules in the middle scales of Lilium davidii var. unicol
or bulb were studied with the scanning electron microscope ( SEM) during the bulb development and storage at
low temperature. The results indicated that a few separate starch granules coexisted with floccules in the cell
beside the big vascular bundle at planting stage. With the development of bulb, the amount of starch granules
increased significantly and reached the maximum at the half withered stage. Furthermore, the shape changes
were observed from sp indle to almost rotundity. For the cells between the big and small vascular bundle, the
amount of starch granules were smaller than that in the cells beside the big vascular bundle. And there are
some cracks on the surface of the starch granule at the vegetative growth stage and bud autumn stage. During
the storage at low temperature, the amount of starch granules tended to decline. By contrastwith the p rocess of
bulb development, the amount of starch granules in the cells between the big and small vascular bundle were
much more than that in the cells beside the big vascular bundle.

Key words: Lily, Lilium davidii var. unicolor, Scale, Starch granule, Ultra-structure