分子标记辅助选择改良武育粳3号的条纹叶枯病抗性

 在对抗水稻条纹叶枯病品种Dular进行抗性基因定位的基础上，以它为抗性供体亲本，武育粳3号为抗性受体亲本，通过杂交和回交，从BC1F1开始利用与条纹叶枯病抗性QTL qSTV 11b和 qSTV 11c 紧密连锁的4个分子标记进行辅助选择，改良武育粳3号的条纹叶枯病抗性和选育抗病新品种。对检测到抗病基因的回交后代进行主要性状的聚类分析，分别有9个抗病基因纯合的BC3F2单株和31个抗病基因杂合的BC4F1单株与武育粳3号聚为一类。经进一步纯合稳定，有望筛选到抗性得到改良、性状回复到武育粳3号的株系。对18个抗病基因纯合的BC2F3株系进行鉴定，其条纹叶枯病的抗性均达到抗的水平，有5个株系丰产性较武育粳3号有明显提高，其中2个株系外观品质也较武育粳3号有了明显改进，达到国家优质稻谷标准。

Improving Resistance of a Good-Quality japonica Variety Wuyujing 3 to Rice Stripe Virus via Molecular Marker-Assisted Selection

A molecular marker assisted selection strategy was used to improve the resistance of Wuyujing 3 to rice stripe disease(RSD). A resistant variety Dular in which two linked QTLs qSTV 11b and qSTV 11c for the resistance to RSD on chromosome 11 were identified in the former research was used as the resistant donor parent and Wuyujing 3 as the recurrent parent. From BC1F1, all the individuals were analyzed with four markers anchoring qSTV 11b and qSTV 11c. The individuals with the bands from Dular were selected for continual backcrossing. From BC2F1, the individuals with the bands of the four markers from Dular was selfed. From BC2F2 the progeny with homologous markers as Dular was harvested. By the dynamic clustering analysis of the backcross progeny, 9 individuals of BC3F2 generation, 31 individuals of BC4F1 generation and Wuyujiang 3 were grouped together. Finally, a number of lines carrying the disease resistance genes have been obtained. Two BC2F3 lines with homozygous disease resistance genotype, which have excellent agronomic characters and output and quality characters have also been obtained.