【摘要】 以稳定遗传的含Cry1Ab基因的抗虫水稻品种镇稻88和含Xa21基因的抗白叶枯病水稻品种圣稻301为亲本进行杂交,利用选择标记基因(bar基因和gus基因)和Southern杂交分析研究了转基因在杂交后代中的遗传分离规律和遗传稳定性。实验结果表明,在杂交后代中选择标记基因bar基因和gus基因分别与抗性基因Cry1Ab基因和Xa21基因紧密连锁并协同表达。Basta抗性检测和GUS活性的组织化学染色检测显示,Cry1Ab基因和Xa21基因在F2代中遵循9∶3∶3∶1的孟德尔遗传规律,F3代的部分株系中Cry1Ab基因和Xa21基因已稳定纯合;对F3代和杂交亲本的Southern杂交分析表明,Cry1Ab基因和Xa21基因可稳定地遗传。通过田间选育,获得了农艺性状优良的双抗(抗螟虫、白叶枯病)转基因水稻新品系SK-1、SK-2、SK-3,3个品系均对二化螟和白叶枯病菌表现出显著的抗性,产量高于镇稻88和圣稻301近20%,品质与镇稻88和圣稻301相近,部分指标优于这两个品种。更多还原

【Abstract】 Two transgenic rice lines: Zhendao88 with Cry1Ab gene and Shengdao301 with Xa21 gene were crossed. The genetic segregation pattern and stability of the transgenes in the hybrid progenies were studied by testing selection marker genes (including bar gene and gus gene) and Southern blot analysis. The result shows that in hybrid progenies the bar gene and Xa21 gene co-inherited and co-expressed, respectively. Basta resistance assay and Gus histochemical staining assay indicated that the F2 generation showed a typical Mendel segregation ratio of 9:3:3:1 and stable homozygotes of Cry1Ab and Xa21 began to appear in the F3 generation. Southern blot assay of F3generation and parental lines showed that the Cry1Ab gene and Xa21 gene could be steadily inherited. By field breeding, we finally acquired 3 transgenic lines with good agronomic traits: SK-1, SK-2, and SK-3, which all showed obvious resistance to stripe stem borer (Chilo suppressalis) and Xanthomonas oryzae pv. oryzae. The yield potentials were about 20% higher than those of Zhendao88 and Shengdao301; the quality was similar and some features were better.更多还原