| Rice is one of the most important crops in the word. It plays also an important role in our country. But its yield per acre has pacing up and down in the past years. It is the main task of the scientists to breed new variey of high steady yield and quality. The two line hybrid rice is a new method of obtaing a super high yield in our country.The discovery and application of the photo-thermosensitive genic male sterility (P/TGMS) system has great potential to revolutionizing hybrid seed production technology in rice. Use of this system in two-line breeding is simple, inexpensive, efficient, and eliminates the limitations associated with the cytoplasmic-genetic male sterility (CMS) system. However, most P/TGMS lines require a specific temperature to maintain their sterility. Abnormal natural weather could bring the temperature down to below the critical level that is required for conversion of TGMS lines from sterility to fertility, simply called fertility conversion, which makes P/TGMS lines fertile or partially fertile in the location where they are supposed to be sterile in normal years. This results in a potential problem for seed production of two-line hybrid rice, i.e. an EGMS line producing seeds from selfing. The mixture of true hybrids with selfed seeds from the EGMS line cannot be used in rice production, resulting in a great loss to seed producers or to rice producers when false hybrid seeds are applied in rice production. Marking the seeds from P/TGMS lines using genetic markers could help remove the false hybrids from the mixture is practical for the safety seed production.Morphological and chemical markers have been investigated as genetic markers to identify real F1 hybrids from selfed seeds (false hybrids) at the seedlings stage. We have got a rice mutant with abilno in first three leaves from the pollen culture of W9461S/W6154S in 1996. Two new male sterility lines with this abino regreening marker have been bred throught crossing and backcrossing, which were named as Bai01S and Bai02S. After some research of this character, the results are as follows:1. These abino regreening regreening genes can exprees steadily in seedlings stage. This abino regreening gene was only expressed in the first three leaves, and recovered from the fourth leaf on. The first leafe was white all over, but the next two leaves were half-part white. Temperature affected the expression dgree of the abino regreening gene. This abino regreening phynotype can bee observed in all temperature regime such as 16, 20, 22, 26 and 30℃. But the plants cultured under 20℃±3 conditions were severer abino than under 25℃±3 conditions. It was consistent with the SPAD of the first three leaves, which was higher under 20℃ than under 25℃.2. This abino regreening character was controled by a pair of simple recessivnucleus gene. Both the Fl from the BaiOlS and BaiO2S crossed with wild type respectively were all green, and Fl with the BaiOlS and BaiO2S as the respective male parent were also all green, and the segregation ratio of F2 was 3:1, showing that the variegated chararcter was controlled by a pair of recessive nuclear gene. When BaiOlS and BaiO2S were pollinated with the pollen of wild type respectively, the same results were observed. It showed that this mutant gene was located on the nuclear genome, and the variegated phenotype was not much influenced by cytoplasm. The further evedent was got from the F3 family.3. This abino regreening characterer had no effect on the growth of sterile line and its Fl hybreeds. The sterility performance of BaiOlS was similar with that of Peiai64S, meaning that this abino regreening phenotype did not affect on the sterility gene of BaiOlS, which came from Peiai64S. But BaiO2S was different from Peiai64S in the sterility expression because of different breeding method. So this abino regreening character can be used as agenetic marker to identify true Fl hybrids from selfed seeds (false hybrids) at the seedlings stage. BaiOlS^ BaiO2S have had such value in that their photosynthesis and other physiology did not change with this abino regreening phenotype.4. This abino regreening charater can be applied in testing the purity of the hybrid rice with a good result of 98.0% in purity. The abino regreening gene of BaiOlS> BaiO2S can express steadily in seedlings stage,and the ratios of purity were 99.9% and 98.6%. It meaned that this this abino regreening mutant character which was transferred to the temperature-sensitive and/or photoperiod-sensitive male serility in rice(TGMS and PGMS) could efficiently used as a morphological marker to sort out the false hybreed seeds.5. This mutant material can be used in the chroloplast genomics researches, such as the relation of chroloplast genome and nucleus genome, the transport machansim of chroloplast protein, and the function of active protein.
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