| Rice (Oryza sativa L.) is one of the most important food crops. It accounts for more than fifty percent of food consumption in China, however, it is vulnerable to the attack of wide range of destructive insects. The fact shows that it is economical and effective to control insects with the insect-resistant varieties, nevertheless which might be bred barely by the traditional methods because of the scarce insect-resistant germplasms. Recent advances in plant biotechnology make it possible to produce insect-resistant rice. Concerns have been raised that the presence of selectable marker genes such as antibiotic or herbicide resistant genes might be unpredictable hazard to the ecosystem as well as to human health, which restricted the development of transgenic work and the spread of transgenic plant. Based on it, an expression vector was constructed with a safe marker gene, 6-phosphomannose isomerase (PMI) that being cloned from E. coli, and an insect-resistant gene, Galanthus nivalis agglutinin (GNA) .Then the plasmid was used in plant genetic transformation. From the experiment, such results below were got:1. The expression vector pCUGNA-PMI was constructed .This vector included an insect-resistant gene GNA from plasmid pCUGNA-bar, a safe marker gene PMI from plasmid pNOV2819 and a report gene GUS from plasmid pCAMBIAlSOl.2. e immature embryos and mature embryos of 10 varieties of rice were inducted, the results of experiment indicated: 1) NB culture medium suits the induction of immature embryos and CC culture medium suits the induction of mature embryos. 2) The effect of cold pretreatment of immature embryos is not obvious, and the treatment time is no more than 3 days. On the contrary, the effect of mature embryos was obvious and suitable treatment can improve the ratio of induction. 3) The first time of subculture is different to different rice variety and different explants. In general, the first time of subculture of immature embryos is earlier than mature embryos. 4) The induction ratio was different with different varieties and different explants. The ratio of immature embryos is higher than which of mature embryos, and the ratio of japonica rice is higher than which of indica rice . 5) The tendence of browning is rely on the following factors: varieties, explants and the first time of subculture.3. he plasmid pCUGNA-PMI and pCUGNA-hyg were introduced into the calli of 10 rice varieties through Agrobacterium tumefaciens-mediated transformation and gene gun-mediated transformation, respectively. The transformation of plasmid pCUGNA-hyg was successful and positive plantlets were acquired by two transformation ways. The ratio of transformation of Nipponbare, ZH9 and DexiangB was much higher than the others among 10 varieties. It is proved that the foreign gene have been integrated into the genome of transgenic rice plants by PCR analysis. However, the transformation of plasmid pCUGNA-PMI was not good enough, the planet can not be obtained by gene gun-mediated transformation and only 14 plantlets were gained by Agrobacterium tumefaciens-mediated transformation, in which only8 plantlets were positive, including 4 Nipponbare plantlets. 3 ZH9 plantlets and 1 501R plantlet.4. he positive plants detected by PCR were analyzed by Southern blotting with random sampling. It suggested that most positive plants gained by Agrobacterium tumefaciens-mediated transformation had only one single site insert in rice genome, while most positive plants gained by gene gun-mediated transformation had several sites insert in rice genome.5 . enetic analysis of the transgenic plant progenies shows that the separating ratio was in accordance with Mendel's single gene inheritance law to most of the positive plantlets being acquired through Agrobacterium tumefaciens-mediated transformation, and there only one site insert in rice genome. However, to most of the positive plantlets being acquired through gene gun-mediated transformation, the segregation ratio of their progenies was not in accordance with the ratio 3:1 becaus...
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