小麦抗叶锈病基因Lr9的分子标记及其检测

1B·1R易位系、高分子量麦谷蛋白亚基(HMW-GS)、多酚氧化酶(Polyphenol oxidase,PPO)活性、黄色素含量等因素都对小麦加工品质有重要影响,慢锈基因Lr34既抗叶锈,又抗条锈、白粉和秆锈病。为了明确这些基因在黑龙江小麦品种中的分布,并为优质抗病小麦分子标记辅助育种提供材料和方法,本研究利用高分子量谷蛋白亚基Dx5、By8、1B·1R易位系、PPO、PSY基因和Lr34位点的特异性分子标记对黑龙江省不同地区的169份小麦品种进行鉴定。结果表明,Dx5亚基的频率为43.2%,By8亚基的频率为30.8%,1B·1R易位系的频率为4.7%,Ppo-A1b的频率为33.1%,Psy-A1b的频率为33.7%,含Lr34位点的频率为24.9%;不含1B·1R易位系、同时又具有Dx5和By8、Ppo-A1b、Psy-A1b及Lr34位点的品种只有2份,占1.2%。

116个小麦品种(系)抗叶锈基因Lr9-Lr26、Lr19-Lr20的复合PCR检测

[目的]建立简单、快速、有效的小麦抗叶锈基因复合PCR体系,从而提高分子标记辅助选择效率。[方法]以28个‘Thatcher’为背景的近等基因系和16个已知基因载体品系作为试材,测试了小麦抗叶锈病基因Lr9、Lr26、Lr19和Lr20的STS标记特异性,通过优化PCR反应体系和循环条件,构建了抗叶锈基因Lr9-Lr26和Lr19-Lr20的复合PCR检测体系。对116个小麦品种(系)所含有的抗叶锈病基因进行了分子检测。[结果]供试品种均不含有Lr9和Lr20,47个品种含有Lr26(基因频率为40.5%),‘中梁22’含有Lr19。经反复验证,Lr9-Lr26和Lr19-Lr20复合PCR技术检测结果可靠,且与上述单个分子标记检测结果一致。[结论]建立的Lr9-Lr26和Lr19-Lr20的复合PCR检测体系可以准确、稳定、高效地检测小麦抗叶锈基因Lr9、Lr26、Lr19和Lr20。

Identification of AFLP Markers Linked to Leaf Rust Resistance Genes Using Near Isogenic Lines of Wheat

The present investigation was undertaken to find molecular markers linked to leaf rust resistance genes, Lr9 and Kharchia local mutant KLM4-3B. Preliminary AFLP analysis was carried out with different stocks, a survey of primer combinations with different selective nucleotide indicated that for each primer combination, the number of scorable loci ranged from 34 to 123. Only a limited primer combination used in the set of parental and near isogenic lines showed a high level of polymorphism for AFLP marker. Putative AFLP marker were found to be linked to Lr9, Lr19 and KLM4-3B. The alien genes were readily identified.

Allelic Relationship between <i>Lr</i>9 and the Leaf Rust Resistance Gene in Kharchia Local Mutant of Wheat

To confirm allelic relationship between Lr9 and the leaf rust resistance gene in KLM4-3B, genetics of resistance was studied using crosses (WL711 + Lr9) × WL711 and (WL711 + LrKLM4-3B) × WL711. The F2 populations in cross (WL711 + Lr9) × WL711 and (WL711 + LrKLM4-3B) × WL711 segregated in ratio of 3:1 for disease reaction at seedling stage against pathotype 77-5 of leaf rust. This suggests that rust resistance in these stocks are under the control of single dominant genes. Further, to study allelic relationship betweenLr 9 and LrKLM4-3B, F2 population of the cross (WL711 + LrKLM4-3B) × (WL711 + Lr9) was studied. A segregation ratio of 15:1 implies that the two genes Lr9 and LrKLM4-3B are non-allelic genes.

Identification of Molecular Markers Linked to Leaf Rust Resistance Genes in Wheat and Their Detection in the Local Near-Isogenic Line

Sixty-five random amplified polymorphic DNA (RAPD) primers were used for the detection of polymorphism among recipient and donor parents and their isogenic lines linked to leaf rust resistance genes, Lr9 and the resistant gene in kharchia local mutant KLM4-3B. Three primers showed polymorphism among recurrent parent, donor parent and isogenic lines.