Floral syndrome and breeding system of Atractylodes japonica

The study on floral syndrome and breeding system of Atractylodes japonica was carried out with the method of fixed-point observation,pollen-ovule ratio( P / O),out-crossing index,bagging pollination,in order to provide the theoretical basis for its resource protection and artificial cultivation. The results showed that flowering period of populations was from late July to early September,the life span of individual inflorescence was 12- 17 d,and the peak period of daily flowering for floret was at 7:00- 8:00 a. m. Pollen vitality was the highest( above 90%) within 2 h,while stigma was no receptivity and its receptivity was the highest after flowering 48- 72 h. The P / O ratio was 6 690,hybrid index was 5,breeding system was xenogamy,and the main floral visitors were bees and flies. There was no apomixes based on bagging and pollination studies,inbred and geitonogamous seed setting rate was low. So,the outcrossing was the major breeding system of A. japonica.