小麦条锈菌国际鉴别寄主Lee对中国条锈菌系CY23的抗性遗传分析

采用常规杂交方法,以国际小麦条锈菌鉴别寄主Lee与感病品种铭贤169杂交、自交、测交,获正、反交的F1、F2和BC1代。根据条锈菌小种的毒性谱,选用CY23单孢菌系,对其双亲及其杂交后代进行苗期抗性鉴定和统计分析,明确抗性基因数目、显隐性、互作方式和抗性特点。结果表明,在正交情况下,Lee对CY23菌系的抗性由1对显性基因和1对隐性基因互补控制,反交情况下也由1对显性基因和1对隐性基因互补控制,正反交分析结果一致,说明Lee对CY23的抗性属核遗传,由1对显性基因和1对隐性基因互补控制。通过对CY23毒性分析和对Yr7、Yr22和Yr23遗传特点研究,表明Lee对CY23抗性的1对显性基因和1对隐性基因分别为Yr7和Yr23,两者互补控制对CY23的抗性。在抗性鉴定中可用CY23区别Yr22与Yr23,并作为标准菌系用于基因推导分析。

Inheritance analysis of wheat yellow rust resistance of the international differential host Lee to Chinese isolates CY23

According to the virulence spectrum of Puccinia striiformis west isolates, race CY23 is used for inoeulation. By simulating the natural conditions during the wheat growing period at seedling stage when the susceptible cultivar Mingxian169 was fully expressed for identification of the stripe rust resistance, the infection types were investigated and the resistance and susceptible phenotypes of seedlings are evaluated. Chi-square tests were employed to analyze the inheritance of the international differential host Lee in order to investigate the number of resistance, the characters of the dominant or the re cessive and the types of gene interaction and resistance. The results showed that by assessing the wheat stripe rust reaction of seedling plants in F1, F2 and BC1 populations of a set of crosses using conventional methods, such as crosses, self-crosses, testing crosses and reciprocal crosses between wheat differential host Lee and susceptible winter wheat cultivar Mingxian169, the resistant plants were obtained following inoculation of F1, F2 and BC1 populations with race CY23, which indieared that a single dominant gene and one recessive gene complementarily determined the reactions of Lee with CY23 under normal temperature, while for the counterpart crossing combinations, a single dominant gene and one recessive gene also determined the reactions of Lee with CY23. The same results implied that the nuclear gene controlled the reactions of Lee with CY23. Through the analysis of the CY23 virulence spectrum and the study of the inheritance of Yr7, Yr22 and Yr23, it showed that the single dominant gene and one recessive gene was Yr7 and Yr23, respectively. They complimentarily determined the resistance of Lee to CY23. As of the resistance characters, Chinese isolates CY23 could distinguish Yr22 from Yr23, which also could be used as the standard isolates for the postulation of genes.