摘要
以含抗性基因Xa2 1和Xa4的抗白叶枯病近等基因系IRBB6 0为供体亲本 ,以不抗白叶枯病强恢复系蜀恢5 2 7为轮回受体亲本 ,连续回交 3代 ,自交 1代 ,在分离世代用分别与Xa2 1和Xa4紧密连锁的标记pTA2 48和MP12对目标基因Xa2 1和Xa4进行辅助选择 ,直至BC3F2 。在BC3F2 中选出株型、粒型、播抽期等农艺性状与蜀恢 5 2 7相似且pTA2 48和MP12的扩增带型纯合的 10个单株 ,用 10 0个RAPD和 12 0对SSR引物进行背景选择 ,决选出 5个单株 ,作为改良的蜀恢 5 2 7。抗性分析表明 ,这些改良的蜀恢 5 2 7株系对我国菌系CⅠ CⅦ和来自菲律宾的P1 和P6 均表现抗性 ,说明抗性基因已成功导入蜀恢 5 2 7中并表达。同时对pTA2 48和MP12在亲本间的多态性和选择的准确性也进行了分析 ,结果显示这两个标记在亲本间的多态性明显 ,共显性 ;选择的准确率分别在 97%和 83%以上 ,可以用其进行标记辅助选择。
Shuhui527'is a promising restorer line bred by Rice Research Institute of Sichuan Agricultural University in recent years. However, this line is susceptible to Bacterial Blight (BB),which limits its use.The IRBB60,from the International Rice Research Institute (IRRI), contains dominant genes Xa21 and Xa4 conferring resistance to BB. The objective of this study is to improve the BB resistance of 'Shuhui527' by introgressing Xa21 and Xa4, the two broad-spectrum BB resistance genes, into 'Shuhui527' with IRBB60 as the donor, pTA248 and MP12, linking tightly with Xa21 and Xa4 respectively as DNA markers. BC 1F 1 progenies of (Shuhui527×IRBB60), containing Xa21 and Xa4 identified using PCR screening and with agronomic traits including plant type,grain type and days to heading etc similar to those of 'Shuhui527', were subsequently backcrossed to 'Shuhui527' and self-pollinated to generate BC 2F 1 and BC 1F 2. The BC 3F 1 and BC 3F 2 were subsequently developed using the same approach.Among the 20 BC 3F 2 plants, homozygous Xa21 and Xa4,10 plants were the most similar to 'Shuhui527' in the agronomic traits, and were screened using 120 pairs SSR and 100 pairs RAPD markers.Based on the results of the background screening and the performance of the agronomic traits,5 plants were identified as improved-'Shuhui527' and designated as 527R-5, 527R-6, 527R-8, 527R-9 and 527R-10.The improved-'Shuhui527' lines expressed high resistance to Xanthomonas oryzae pv.oryzae (Xoo) stains CⅠ-CⅦ, P 1 and P 6. The evaluation of the polymorphisms and selection accuracies of pTA248 and MP12 demonstrated that the polymorphisms of the two markers were obvious and co-dominant and the accuracies were more than 97% and 83% respectively, indicating the two markers are good for Xa21 and Xa4 in Molecular Marker-assisted Selection.
出处
《生物工程学报》
CAS
CSCD
北大核心
2003年第2期153-157,共5页
Chinese Journal of Biotechnology
基金
国家 8 6 3高技术发展与研究计划项目 (No .2 0 0 1AA2 110 81)
教育部优秀博士论文基金 (No .2 0 0 0 5 4)。~~
关键词
抗白叶枯病
分子标记辅助选择
抗性鉴定
水稻
白叶枯病
选育
Xa21, Xa4, bacterial blight resistance, molecular marker-assisted selection (MAS), resistance evaluation
