| Blast is a fungus disease of rice. Using lysozme and npt-II gene as the external genes, transforming by bombardment, by continuous five-year selection and breeding and blast-resistance experiments, Institute of genetics and developmental Biology, Chinese Academy of Sciences obtained Transgenic rice D 2-1-2 (Zhonghua 9 ZH9 (R) ). The analysis showed that it was immune to 37 physiological races of blast. Using the transgenic ZH9 (R) as donor, restorer lines 9311, MH63, 288, E32 and male sterile line PA64s as receptor , restorer lines and male sterile line with lysozme will be developed. Resistant restorer lines crossing male sterile line will obtain good super-hybrid rice that are resistant to blast.(一) Research on quick testing-technology of transgenic rice with npt -II screen marker geneBy using npt- II in ZH9 (R) as auxiliary selection-marker, conducting ZH9 (R) and ZH9 (CK) with antibiotic, we built a system of quickly testing transgenic rice offspring.Detached leaves of ZH9 (R) and ZH9 (CK) were treated by Kanamycin and G418 with different concentration. When Kanamycin was 700 mg/1, on the sixth day, the leaves of ZH9(R)and ZH9(CK)were not damaged. When G418 was 80mg/l, on the fourth day, the leaves of ZH9 (CK) had been yellow and dead, but the leaves of ZH9 (R) remained green. Therefore, G418 was selected as the optimal antibiotic and 80mg/l was treated as the optimal critical concentration to test detached leaves of transgenic rice. Further study indicated: 300mg/l was the best critical concentration to test seeds of transgenic rice; 200mg/L was the best critical concentration to test young embryo of transgenic rice;150mg/Lwas the best critical concentration to test seedlings of transgenic rice.Two primers were designed based on npt- II and iysozme gene sequences. PCR was done to confirm the above detection system. Results showed the wpt-II was closely linked with lysozme gene. Above confirmed critical concentrations were adopted to select detached leaves, seeds, young embryos and seedlings of transferred offspring. Hie effect was very significant. By x testing, the separation law of backcrossed offspring was 1:1 and one of self-crossed offspring was 3:1, which was coincident with Mendelian genetic law. So external lysozme gene was single-copied, dominant and stably genetic.(二) Research on ZH9(R) transferring different hybrid rice parentsZH9(R ) crossed with excellent restorer lines 9311, MH63, 288, E32 and sterile line PA64s, which produced FI generation. Then 9311 , MH63, 288 , E32, PA64s as rotation parents, disease-resistance gene of Lysozme was transferred. The main conclusions are described as follows:(1) G418 testing is consistent with PCR, PCR-Southern testing. Transferring offspring were tested with G418 and PCR. Positive plants of G418 had the same amplifications as one of lysozme gene. Furthermore, PCR conclusion was proved correctly through PCR-Southern. G418 testing is consistent with blast-resistance. 99% of G418 positive plants wete resistant through resistance evaluations.(2) PeiLiangYou 288 as induction variety, rotation parents, transferring generations, hybrid rice and testcrosses were evaluated in rice blast nursery. Combined with inoculation and induction, the effect is satisfactory. The disease-resistance ability of transferring generations was stronger than one of rotation parents. The disease-resistance ability of testcrosses also had been improved greatly compared with corresponding hybrid rice.(3) Investigation on agronomic characters of transferring progenies and rotation parents were made. With the generations increasing, the agronomic characters of backcross progeny are closer with parents. That is to say, all agronomic characters ofBC1F1 have significant differences with rotation parents; some agronomic characters of have significant differences with parents; none of BC3F1 has significant differences with them.(4) Domination of transferring generations was examined. The agronomic characters of testcrosses were worse than one of hybrid rice,...
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