分子标记辅助选择改良水稻不育系‘荃211S’白叶枯病的抗性

本研究旨在提高优质两系光温敏型核不育系‘荃211S’的白叶枯病抗性。以‘荃211S’为受体亲本,以含有抗白叶枯病Xa23基因的CBB23为供体亲本,通过分子标记辅助选择技术与常规育种技术相结合,筛选抗白叶病的不育株系。筛选出4个改良不育株系QK211S-1~QK211S-4。改良‘荃211S’株系的农艺性状、育性转换温度、异交结实率与‘荃211S’相近,但在白叶枯病抗性上明显增强,表现出高抗或抗,抗性级别0~2。改良‘荃211S’株系所配组合与‘荃211S’所配组合在株高、每穗总粒数、结实率、千粒重的差异不显著,但白叶枯病抗性显著增强,抗性级别为1,高抗。改良的4个‘荃211S’株系为选育抗病水稻品种奠定了基础,可以直接在生产中应用。

Bacterial Blight Resistance of Rice Sterile Line ‘Quan 211S’ Improved by Molecular Marker-Assisted Selection

This study aims to improve the bacterial blight resistance of photo-thermo-sensitive genic male sterile ‘Quan 211S’ with high quality. Using ‘Quan 211S’ as the recipient parent and ‘CBB23’ containing Xa23 gene as the donor parent, the sterile lines resistant to bacterial blight were bred by combining molecular marker-assisted selection technology with conventional breeding technology. Four improved sterile lines, from Qk211s-1 to Qk211s-4 were selected. The agronomic characters, fertility alteration temperature and outcrossing setting rate of the improved lines of ‘Quan 211S’ were similar to those of ‘Quan 211S’, but the resistance to bacterial blight was significantly enhanced, showing high resistance or resistance, and the resistance level was 0-2. The combinations of improved lines of ‘Quan 211S’ had no significant differences in plant height, grain number per panicle, seed setting rate and 1000-grain weight compared with those of the combinations of ‘Quan 211S’, but the resistance to bacterial blight was significantly enhanced, showing high resistance, and the resistance level was 1. The four improved lines of ‘Quan 211S’ can lay a foundation for breeding disease resistant rice varieties and be directly applied in production.