Abstract: Lycoris radiata was used as the experimental material,and the paraffin section microscopic observation method and Image-Pro Plus statistical software were used for comprehensive analysis in this study.The effects of the temporal and spatial distribution of starch grains in Lycoris radiata bulb on its growth and development were studied,in order to provide reference for further clarifying the’Source-Sink’ conversion law and dormancy mechanism of Lycoris radiata bulbs.The results showed that there were significant differences in the distribution density of starch grains in different parts of the bulb,and the overall pattern was middle scale＞inner scale＞bulb disc＞outer scale.In the same scale,the distribution density of starch grains decreased gradually from the outside to the inside.In the process of annual growth and development,the number of starch granules in the scale decreased first and then increased,while the area and particle size of starch granules showed the opposite trend.The number and particle size of starch granules in bulb plate not change significantly.At six different developmental stages,the average size and area of starch granules in bulblets was significantly smaller than those in scales.This indicated that the above-ground growth and development of Lycoris radiata was related to the changes of starch granules in underground bulbs.The growth and development of Lycoris radiata was a process of energy consumption,and its energy supply was related to the attribute change of underground bulb starch granules.Nutrient growth was positively correlated with the accumulation of starch granules in scales,while reproductive growth was positively correlated with the size of starch granules.That was to say,that bulbs mainly play the function of ’Source’ in full bloom stage,while bulbs mainly play the function of ’Sink’ in leaf growth stage.