小麦遗传背景对黑麦抗叶锈基因Lr26的抗性表达的影响

利用1套从小麦纯系和黑麦自交系培育出的1R附加系、代换系和易位系,研究了1RS上的抗叶锈基因Lr26在小麦中的表达。结果发现,1R二体附加系和纯合1RS/1BL易位系高抗小麦叶锈病;而其小麦亲本、1R(1B)代换系和1BS/1RL易位系重感叶锈病。这一结果指出了黑麦染色体臂1RS上的抗小麦叶锈病基因Lr26在小麦中的表达受小麦染色体臂1BL上的基因的强烈影响,指出了外源基因在小麦中的表达可受染色体臂或基因水平上的相互作用的制约。文中讨论了外源基因与小麦遗传背景相互作用在小麦育种中的意义。

Effect of Wheat Genetic Background on the Expression of the Rye Gene Lr26 for Resistance to Leaf Rust in Wheat

The gene Lr26 on rye chromosome arm IRS was defined as a gene resistant to-leaf rust in wheat. The expression of this gene in wheat was investigated by using a set of rye 1R addition, 1R/1B substitution and translocation lines developed from a rye inbred line R15 and a wheat pure line SP322, which were highly susceptible to leaf rust. In this study it was found that the 1R addition line (2n - 44 - 2l"W + 1"1R) and 1RS/1BL translocation line (2n - 42 - 20"W + 1"1RS/1BL) showed a strong resistance to leaf rust, whereas the substitution line (2n - 42 - 20"W + 1"1R) and 1BS/1RL translocation line (2n - 42 - 20"W + 1"1BS/1RL) were infected seriously with Puccinia recondita i. sp. tritici. The results indicate that a gene on wheat chromosome arm 1BL would have a strong influence upon the expression of the gene Lr26 on rye chromosome arm IRS in wheat. The interaction of alien genes with the genetic backgroud of the wheat genome in relation to breeding of wheat is discussed in this paper.