| Selection of photo-thermoperiod sensitive genie male sterile (P/TGMS) lines in rice is the key factor for the successful utilization of two-line hybrid rice, in which seed contamination originating from cross pollination with exotic pollen and mechanical seed mixture cause a decrease in purity of male sterile seeds and its hybrid seeds. To overcome such problems, the phenotype marker traits, such as pale-green leaf and purple leaf, have been used in breeding indica P/TGMS lines. In this research, several japonica P/TGMS lines with a pale-green leaf marker were firstly studied, and the content of the thesis are as follow: the fertility transformation of P/TGMS with pale-green leaf marker under natural condition; the inheritance of leaf color and male sterility; the effects of such traits toward agronomic traits; the combining ability, flowering habit and photosynthetic characteristics of P/TGMS lines. The main results are summarized below.1. The fertility transformation of TS1 was mainly controlled by temperature. The correlation of daily minimum temperature with the fertility was the most significant, followed by daily mean temperature and daily max temperature. The temperature sensitive stage of TS1 and PA64S (CK) were 3-18d and 6-21d before heading respectively, and the critical temperature of the fertility conversion were 25.78'C-25.79 C and 24.41C-25.61C. The fertility transformation of pale-green leaf sterile lines was easily influenced by the differernce of temperature between two years.2. F2 populations generated by the hybridization between pale-green leaf sterile lines and restore lines were used to study the inheritance of leaf color and male sterility. Of all the F2 populations, the segregation of leaf color was 13 (green): 3 (pale-green), implying the leaf color was controlled by two genes, and one gene inhibited the other. The leaf color distribution in F2 populations showed two successive apices, approving the inheritance of rice leaf color accorded with two genes model. The segregation of fertility in the first stage was also 13 (fertility): 3 (sterility), which according to the two genes model. The fertility dispersion in F2 populations was quite complicate. Every combination showed different distribution according to different parents and sowing stages. Of all the fertility distribution curves in F2 populations, some had one main apex with several mini effect apices, others had two or three main apices. It was concluded that the male sterility was controlled by two main effect genes cooperated with other mini effect genes. The pale-green leaf color had no significant negative effect on main agronomic traits of rice.3. Difference of the combining ability of parents showed the additive effect was dominant for all measured traits. For the pale-green leaf sterile lines, TS3 had the best general combining ability which was very close to ZAU11S (CK), while Waa24 was the best for the restoring lines. The general combining ability of the restoring lines was higher than that of sterile lines in the most of the measured traits. The general combining ability and the specific ombining ability of the traits are relative independent.4. The flowering duration, flowering rate and stigma exsertion rate of pale-green leaf sterile lines were all lower than ZAU11S (CK). There were great differences among pale-green leaf sterile lines in daily flowering rate, spikelet opening time and opening angle of spikelet. Pale-green leaf sterile lines had the higher flowering rate in the morning in sterile stage, but a few flowers in the afternoon except ZAU11S. All sterile lines had a central flowering duration with the notable flowering apices in fertile stage. Pale-green leaf sterile lines flowered early both in sterile stage and in fertiltiy stage at 9:00 or 10:00 a.m except TS1.5. By testing the chlorophyll content, photosynthetic rate (Pn), soluble protein content and rubisco content in three developmental stages (tillering stage, heading stage and ripe stage), chlorophyll content and photosyntheti...
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