利用基因聚合技术改良一个优质水稻不育系的稻瘟病抗性

以抗稻瘟病水稻材料金山B-1抗病近等基因系05AMA59(携有稻瘟病抗性基因Pi-1)、05AMA71(携有稻瘟病抗性基因Pi-9)为抗性供体亲本,通过分子标记辅助回交和聚合杂交,将Pi-1、Pi-9基因导入花紫A(B)中,并在选择加代过程中改良其稻瘟病抗性.(1)遗传背景分析表明,Pi-1和Pi-9基因已成功导入新育成的不育系益农A(B)中,其遗传背景基本恢复为轮回亲本花紫A(B)的遗传背景;(2)益农A(B)的室内和田间自然诱发鉴定均表现抗病,抗性水平和抗谱均明显高于感病对照花紫A(B);(3)益农A与原来的花紫A在生育期、株高、穗粒数等重要农艺性状以及柱头外露率、异交结实率等方面均相似,益农A与花紫A所配的杂种一代在产量、株高、生育期等主要农艺性状上也相近,表明益农A保留了花紫A配合力高、米质优、异交率高等优良特性.

Improvement of the resistance to rice blast in a high quality rice CMS line by gene pyramiding

Using 05AMA59 and 05AMA71(two near-isogenic lines of Jinshan B-1,carrying rice blast resistant gene Pi-1 and Pi-9 respectively) as the donor of resistant genes,the Pi-1 and Pi-9 genes were introgressed into a good maintainer line Huazi B via marker-assisted backcross breeding and gene pyramiding,and a new CMS line Yinon A was bred.The results were as follows:(1) The foreground and background analysis showed that,Pi-1 and Pi-9 gene had been successfully imported into Yinong A(B),the basic genetic background of Yinong A had been restored for the Huazi A(B) genetic background.(2) The resistance identification of laboratory and field showed that the resistant level and resistant spectrum of Yinong A(B) were significantly higher than that of the susceptible control and Huazi A(B),which showed that our study on improving blast resistance was successful.(3) The main agronomic traits of Yinong A(B),such as growing period,plant height,grain number,exserted stigma,outcrossing rate,etc,were similar to those of Huazi A(B),and there was no significant difference in main characters of F1,such as yielding,growing period,plant height between Huazi A and Yinon A too.The result indicated that Yinon A was characterized by the excellent features such as good combining ability,good grain quality,high stigma exsertion and high outcrossing rates.