Analysis of Natural Mutant of Photoperiod Sensitive Genetic Male Sterile Japonica 920S under Different Photoperiods in Rice

Photoperiod sensitive genetic male sterile (PGMS) rice 920S was characterized as sterile when it was grown under long day condition but fertile when grown under short day condition. PGMS rice 920S, F1 and F2 plants were examined for their fertilities under different photoperiods. All 920S parent plants were fertile in short photoperiod condition at 10 hrs day length, partial fertile in intermediate photoperiod condition at 13 hrs day length and sterile in long photoperiod condition at 14 hrs day length. However, F1 plants were fertile in long photoperiod condition contrary to their parent and F2 populations. Interestingly, F2 plants showed wide range of fertility with partial segregation of complete fertile, partial fertile, and complete sterile plants when they were exposed to intermediate day length condition of 13 hrs day length. Therefore, here we suggest that there is a critical photoperiod to affect a PGMS gene that causes an alteration in fertility.