Abstract: The changes of carbohydrate accumulation in leaves and stems of the Zizania latifolia were studied on two typical varieties at their different growth and development stages. The allocation of photosynthesis assimilates in different organs was also determined by using ¹⁴C-labeling technique. The results showed that , before the Zizania gall expanding , the accumulation of total sugar , reducing sugar and starch increased continuously and the greatest amount of carbon assimilates were observed to be accumulated in the culm , as compared with that in other organs. When Zizania gall began to expand , the carbohydrate in other organs stopped accumulation. Most carbohydrates stored in culm were remobilized. The culm serves as stored organs for remobilized assimilates to the growth of Zizania gall . Starch is the main formfor stored carbohydrate , and most of ¹⁴C assimilates was prefixed in culm before pregnant . The accumulated carbohydrate in the up leaf and sheath of plant was higher than that of its low leaf and sheath. During the period of Zizania gall expanding , most of prefixed-¹⁴C was remobilized into gall . The labeled assimilates fixed by leaves supplied not only for its straws but also for the other parts of the plant .

Key words: Zizania latifolia Turcz., Carbohydrate, ¹⁴C tracer