On seed dormancy in photoperiod (Thermo-) sensitive genetic male sterile rice Peiai64S

In order to gain the index of detecting seed and regulating the seed dormancy and seek for the effective method of breaking seed dormancy,the seed dormancy of PGMS Peiai 64S is studied through testing the germination frequency of the dormant seed continuously and termly with several physical and chemical methods.The results show that the seed of Peiai64S has a characteristic of deep dormancy.The dormant period of seed(its germination percentage was less than 80%) multiplied in summer from Hunan and in spring from Hainan were respectively about 45 days and 60 days,and the complete dormant period (its germination percentage was more than 99%)are 77 days and 105 days respectively.The difference of dormant period among Peiliangyou288, Peiliangyou500 and Peiai64S is not significant, and the dormancy of seed isnt correlative to the absorbing-water rate.at seed dormancy.Its anylase activities of -amylase and + amylase are lower than the ones in undormancy.The treatments of high temperature(40 ℃,50 ℃),GA3 ,H2O2 and Qianglvjing solution are effective to brenk seed dormancy.Furthermore,the treatment of Qianglvjing solution of 1∶250 which is 250 times,is the simplet and the most effective method .