| Two-line heterosis breeding based on photo-thermoperiod sensitive genie male sterility (P/TGMS) has the main advantages, including the ability to use a wide range of genotypes as male parents, absence of negative effects associated with sterility-inducing cytoplasm, ho need for maintainer lines, and created a new way for the use of heterosis. But the male sterile trait is easy to be influenced by unpredicted low temperature during its fertility sensitive stage, it decrease seed purity of hybrid rice and limit the development of hybrid seed production. So it is very important for the theory and practice to research and insight the fertility alteration, fertility inheritance and physiological and biochemical characters of PTGMS lines. In this paper, F2 and F3 populations from two PGMS lines with the pale-green leaf marker (TS1, TS3) and four different restorer lines in japonica rice, and several PGMS lines bred newly by our group from the cross between Xiushui63 and ZAU11S was observed as the materials, by chlorophyll content of each plant in eight F2 populations tested using SPAD instrument made in Japan, the sterile and fertile standard according to 5% natural seed-set percentage in each F2 population at the mature stage and using naked eyes observation, the pale-green leaf and fertility inheritance were analyzed; Under the natural conditions in Hangzhou, fertility alteration of five PGMS lines was observed and the determination of the sensitivity to photoperiod and temperature among several newly lines was insighted based on the AMMI(additive main, effects and multiplicative interaction) model, linear regression model and hierarchical cluster analysis under the nine sowing date; in the end, the physiological and biochemical characters and pollen sterility mechanism for PGMS line were discussed. The main results are as follows:The pale-green leaf color was controlled by two pairs of genes, of which there was a suppressing gene, the pale-green leaves as a marker trait is caused by lacking of the dominance-suppressing gene (I), and that the male sterility was controlled together by two major effect genes with several minor genes. Both the leaf color and male fertility were inherited independently. By firstly using the method of cumulativedistribution curve in pale-green leaf trait we proves that the inlieritance model of pale-green leaves in F3 of the combination TSl/Waa24 accords good with the two genotypes theory curve of AB.The data of two criterions, pollen and seed fertility, was analyzed on the eleven P (T) GMS based on AMMI model, linear regression model and hierarchical cluster analysis under the nine sowing date in 2003. The results demonstrated that there were significant differences in the pollen and seed fertility for genotypes, sowing date and their interaction. The results of main effects and interaction effects analysis were different between the two criterions, the authors suggested that it was reasonable to study on the fertility alteration according to bagged seed set. The sterility stage, fertility alteration stage and fertility stage were classified, the photo-sensitive sterile lines and thermo-sensitive sterile lines were distinguished by analysis of genotype main effects and interaction effects by AMMI model, also offered information and proof for the application of P (T) GMS lines. The parameter, Dit had been proposed to measure the fertility stability of P (T) GMS rice in this paper. The research results indicated the estimates of D, were feasible and greatly concordant with the breeding practice.Five japonica {Oryza sativa L.) PGMS lines backcrossed from ZAU11S, were sequentially seeded with lOd interval at Hangzhou, China in 2003 and 2004 year. The results of investigations on pollen fertilities and spikelet fertilities showed that the fertility of all five lines was sensitive to photoperiod mainly, temperature effect was smaller and correlation coefficient between daily minimum temperature and fertility was significant. The critical point of photoperiod was 13.51~14.0 hr, the most sensitive stage was from secondary branch and floret primordium differentiation to pollen mother cell formation and the photoperiod sensitive stage was longer. The sensitive stage to photoperiod and temperature was different according to different sowing date and genotypes, the temperature sensitive stage and critical point temperature was needed to be identified further using growth chamber. The sterile stage more than 30 days was longer and stable compared with the control. The tested sterile lines T7, T8 and T9 had potential utilization value in production according to...
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