Winter cultivar'Yidianhong'and spring cultivar'Duanye 13'were used to study the carbohydrate content of stem apices and leaves during the progress of floral bud differentiation.Germinated radish seeds were subjected to chilling at 5℃ for 20 days.After low temperature treatment,all seedlings were transplanted into glasshouse under warm(>15℃)and long photoperiod(16 h)growth condition. Amounts of total soluble sugars,sucrose and starch were assayed during the various floral bud differentiation stages.The fo...