Abstract: Controlled temperature and photoperiod experiments with two day/night temperature (31/22℃,27/22℃) and 6 photoperiods (10.0,12.0,13.0,13.6,14.0 and 15.0 hours)were conducted in a phytotron to observe the influence of photoperiodic treatments on temperature effect level of 3 varieties of PGMS rice. The results indicate that under the temperature regime the male fertility of controlled variety is completely normal, but the conversion between SD-fertility and LD-complete sterility can occur in PGMS rice, a drop of 4℃ in temperature can lead to their temperature effect, and result in a significant decrease of their male sterile degree under different photoperiods. The temperature effect level varies significantly with different photoperiods, which increases abruptly with the shortening of day length, and tends to negatively correlated with day length. It is implied that by means of breeding PGMS rice with shorter sterile critical day length and artificially regulating the relationship between practical day length and sterile critical day length,it is possible to reduce the influence of temperature and to stabilize the male sterile level of PGMS rice.

Key words: Rice, Male sterility, Photoperiod, Temperature effect, Interaction between photoperiod and temperature, methanotroph., methane, Spartina alterniflora, coastal salt marsh, methanogen