源于易变山羊草的小麦抗条锈病基因的分子标记与育种利用

Puccinia striiformis f. sp tritici (Pst), the causal agent of wheat stripe rust (also known as yellow rust), is a serious threat to global wheat production. The stripe rust resistance from major Yr genes used in wheat production can be quickly overcome, because of the frequently mutations of the pathogen populations. A possible solution for this problem for a long-term strategy is to explore and utilize new Yr genes with durable resistance by pyramiding adult plant resistance. We previously transferred a dominantly adult-plant resistance gene from Aegilops variabilis into common wheat. In the present study, we will map this Yr gene, develop its closely linked PCR markers, and transfer it into the major wheat varieties with the help of PCR markers. Our purpose is to provide new gene resources and selection markers for further wheat resistance breeding.

小麦条锈病是威胁着小麦生产的一个主要世界性病害。条锈病新小种的出现, 导致多数主效基因抗性丧失, 目前小麦育种缺乏抗源。发掘和利用新的抗条锈病抗源，培育推广含成株期抗性抗病基因，抗性持久的小麦品种被广泛认为是控制条锈病的一个长效措施。我们前期将野生物种易变山羊草的成株抗条锈病基因导入小麦, 获得了抗病的稳定品系，该抗性受一对显性基因控制。本项目旨在：定位该外源基因, 开发紧密连锁、易于追踪检测的PCR标记, 并将该基因导入小麦主栽品种中，为小麦育种提供新抗源及选择标记。

小麦条锈病是威胁着小麦生产的一个主要世界性病害。条锈病新小种的出现, 导致多数主效基因抗性丧失, 目前小麦育种缺乏抗源。发掘和利用新的抗条锈病抗源，培育推广含成株期抗性抗病基因，抗性持久的小麦品种被广泛认为是控制条锈病的一个长效措施。我们用高抗条锈病易变山羊草AS24和感病小麦品系3854杂交回交后，连续多代自交获得含有易变山羊草抗条锈病基因高代抗病品系（NZ238）和感病品系（NZ242）。利用这两个品系杂交构建了F2分离群体及其F2:3家系。结果表明，抗病性是由一对显性基因控制，小麦2AS缺失片段（14.2-20.0Mb）上的4个分子标记与抗病基因连锁。获得超过30份F5/6代改良品系，其中品系蜀麦2105正参加本单位小麦品比试验。