Genetic Analysis Of Fertility Response To Photoperiod And Temperature In Photoperiod And Thermo-Sensitive Genic Male Sterile Rice

In order to get a better understanding of the fertility reaction to photoperiod and temperature of the photoperiod and thermo-sensitive genic male sterile [P(T)GMS] gene that major control the fertility conversion, Japonica PGMS rice and Indica PTGMS rice were selected as material. In the condition of artificial control of photoperiod and temperature, the fertility response to photoperiod and temperature of hybrids F1,the fertility segregation ration of F2, the fertility reaction to photoperiod and temperature of sterile plants in F2 and fertility genetic stability of offspring were studied. The main results are as follows:The fertility of hybrid F1 of NK58S and its derivatives PGMS lines were photosensitive, and the fertility of hybrid F1 of P(T)GMS lines which derived from NK58S were non-photosensitive. The hybrid F1 of NK58S(Japonica PGMS line)/7001S (Japonica PGMS line),7001S/ Guangzhan63S(Indica PTGMS b line),ChangguangS (indica PGMS line)/Pei'ai64S[indica P(T)GMS line] were sterile, and the sterile gene was allelic. Under the short daylength induction, F1 were converted to fertile. The fertility of hybrid F1 is photosensitive. The hybrid F1 of Guangzhan 63S/Pei'ai 64S was sterile, and the sterile gene was allelic. In the short daylength induction, it remains sterile. The fertility is not photosensitive. Most of the fertility of sterile plants, which separated from hybrid F2 of NK58S and its derivatives PGMS lines, were sensitive to photoperiod. At the same time, Most of the fertility of sterile plants separated from hybrid F2 of P(T)GMS lines that derived from NK58S, were not sensitive to photoperiod. The segregation population of NK58S/7001S,7001S/Guangzhan 63 S,Changguang S/Pei'ai 64S and Guangzhan 63S/ Pei'ai 64S were sterile. After induction of short daylength to sterile plants in segregation population,88.41% sterile plants of the NK58S/7001S hybrid F2 were converted into fertile plants, showing that they are photosensitive. At the same time, only 7.01% sterile plants of the 7001S/Guangzhan 63 S hybrid F2 exhbited fertility photosensitive, 9.61% sterile plants of Changguang S/Pei'ai 64S hybrid F2 are fertility photosensitive. The sterile plants of the Guangzhan 63 S/Pei'ai 64S hybrid F2 are not photosensitive.The photosensitive sterile plants of NK58S and its derivatives PGMS hybrid F2 have a high genetic stability in terms of fertility photosensitivity. On the contrary, the photosensitive sterile plants of hybrid F2 of PTGMS lines which derived from NK58S have a low genetic stability in terms of fertility photosensitivity.The Y58S is a elite P(T)GMS rice line in hybrid rice seed production. The research indicates that the critical sterility-inducing temperatures of every single plant in the group are obviously different, and the tolerance to stress of low temperature is different between the sterile plants. Therefore, by way of artificial selection in low temperature stress selecting core sterile plants, and then to product Rice Basic Seed, the critical sterility-inducing temperature of P(T)GMS could be reduced and the fertility stability increased.