甘蓝型油菜杂交种圣光168父本根肿病抗性的遗传改良与应用

为培育优良的抗根肿病油菜品种，以华双5R和华油杂62R（分别携带抗根肿病位点PbBa8.1和CRb）为供体亲本，以圣光168的父本Y522R为轮回亲本，通过回交与分子辅助育种相结合，将PbBa8.1和CRb导入到Y522R中，选育出遗传背景回复率均达90%以上，且分别携带PbBa8.1、CRb和PbBa8.1+CRb抗病位点的近等基因系Y522R ^PbBa8.1 、Y522R ^CRb 、Y522R ^PbBa8.1+CRb，并在此基础上与圣光168母本RG430A配制了具有根肿病抗性的改良杂交种圣光168CR ^PbBa8.1 、圣光168CR ^CRb 和圣光168CR ^PbBa8.1+CRb。利用我国根肿菌4号优势生理小种，对改良株系及杂交种进行苗期根肿病抗性鉴定，结果表明：Y522R ^PbBa8.1+CRb 和Y522R ^CRb 改良株系及其改良杂交种圣光168CR ^CRb 和圣光168CR ^PbBa8.1+CRb 对4号生理小种具有免疫抗性；Y522R ^PbBa8.1 改良株系及其改良杂交种圣光168CR ^PbBa8.1 对4号生理小种表现为感病，但显著低于对照Y522R及圣光168。农艺性状考察结果表明，Y522R改良株系及其改良杂交种的开花期、株高、有效分枝数、角果长、每角果粒数和千粒重都与对照无显著性差异，说明这些改良杂交种可作为重要的抗根肿病油菜资源。

Genetic improvement and application of resistance to clubroot in male parent of Brassica napus hybrid Shengguang 168

To improve rapeseed resistance to clubroot, Huashuang 5R （carrying PbBa8.1 locus） and Huayouza 62R （carrying CRb locus） were used as donor parents for transferring resistant genes into Y522R. The strategy was combined with successive backcross and marker-assisted selection. By the process, 3 near isogenic lines Y522R ^PbBa8.1, Y522R ^CRb and Y522R ^PbBa8.1+CRb （containing PBba8.1, CRb, and PbBa8.1+CRb respectively） were obtained, with more than 90% genetic background recover rate. Subsequently, 3 clubroot resistant new hybrids Shengguang 168CR ^PbBa8.1, Shengguang 168CR ^CRb and Shengguang 168CR ^PbBa8.1+CRb were derived from these near isogenic lines and RG430A （female parent of Shengguang 168）. The clubroot resistance of the above lines （as Y522R ^PbBa8.1, Y522R ^CRb, Y522R ^PbBa8.1+CRb,Shengguang 168CR ^PbBa8.1, Shengguang 168CR ^CRb and Shengguang 168CR ^PbBa8.1+CRb ） was identified by using Race 4 （the dominant physiological race in China）. Results showed that Y522R ^CRb, Y522R ^PbBa8.1+CRb and their hybrids （Shengguang 168CR ^CRb and Shengguang 168CR ^PbBa8.1+CRb ） had immunity to Race 4. Although Y522R ^PbBa8.1 and hybrid Shengguang 168CR ^PbBa8.1 were susceptible to Race 4, their levels of the resistance were still significantly higher than those of the control （Y522R and Shengguang 168）. Evaluation of agronomic traits showed that no significant differences were observed between the improved lines and Y522R, neither between the improved hybrids and Shengguang 168. The traits included flowering days, plant height, effective branches, silique length, seeds per silique and thousand seeds weight. Thus laid an important foundation for cultivation of excellent rape varieties resistant to clubroot.