The Approach of Breeding Japonica Photo-thermo-sensitive Genic Male Sterile Rice Adapting to Climate Condition of the North of China

The response to photoperiod and temperature of different types P(T) GMS rice (photo-thermosensitive genie male sterile rice), were studied by means of treating light length in pots and sequential sowing in fields. The results indicated that P(T)GMS rice tested were classified into two types: P(T) GMS and thermosensitive genie male sterile (TGMS) rice according to condition inducing fertility alteration (FA). The P(T)GMS rice,for example Nongken 585, was induced sterility under long light length and high temperature (HT),and fertility under short daylength and low temperature (LT). The FA in TGMS rice was mainly controlled by daily average temperature at sensitive phase but not by photoperiod.The TGMS rice was subdivided Into the positive TGMS(P-TGMS) rice and the negative TGMS(n-TGMS)rice. The P-TGMS rice were induced sterility by HT and fertility by LT.In contrast with P-TGMS rice,the n-TGMS rice were fertile under HT and sterile under LT.In contrast with P-TGMS rice, the n-TGMS rice were fertile under HT and sterile under LT. The criticaltemperature for FA of Hengnong-3S was about 27℃,i.e. fertility above 27℃ and sterility below 27℃. The tatics of breeding pratical japonica P(T) GMS adapting to the north were suggested.