Li Qiang, Huang Jing, Hou Lu, Liu Pei, Jing Jinxue, Wang Baotong, Kang Zhensheng
State Key Laboratory of Crop Stress Biology for Arid Areas/College of Plant Protection, Northwest A&F University, Yangling 712100, China.
Plant Dis. 2012 Oct;96(10):1482-1487. doi: 10.1094/PDIS-03-11-0204-RE.
Stripe rust, caused by Puccinia striiformis f. sp. tritici, is one of the most important diseases of wheat worldwide. The best strategy to control stripe rust is to grow resistant cultivars, but only a few effective genes are available. The wheat accession H9020-1-6-8-3 is a translocation line previously developed from interspecific hybridization between wheat genotype 7182 and Psathyrostachys huashanica, and is resistant to most Chinese Puccinia striiformis f. sp. tritici races. To identify the resistance genes in the translocation line, H9020-1-6-8-3 was crossed with susceptible genotype Mingxian 169, and seedlings of parents and F, F, and F progenies were tested with prevalent Chinese P. striiformis f. sp. tritici races CYR32 and CYR33 under controlled greenhouse conditions. The genetic results indicated that two single dominant genes in H9020-1-6-8-3 confer resistance to CYR32 and CYR33, respectively. The gene for resistance to CYR33 was temporarily designated as YrH9020. Six simple-sequence repeat markers were used to map the resistance gene to the short arm of wheat chromosome 2D, using 329 F plants tested with CYR33 in the greenhouse. The genetic distances of the two closest flanking markers, Xgwm261 and Xgwm455, were 4.4 and 5.8 centimorgans, respectively. Disease assessments and polymorphic tests of the flanking markers among the Psathyrostachys huashanica line and wheat lines 7182, H9020-1-6-8-3, and Mingxian169 suggested that the resistance gene YrH9020 in H9020-1-6-8-3 was originally from P. huashanica. The exotic stripe rust resistance gene and linked molecular markers should be useful for pyramiding with other genes to develop wheat cultivars with high-level and durable resistance to stripe rust.
条锈病由条形柄锈菌小麦专化型（Puccinia striiformis f. sp. tritici）引起，是全球小麦最重要的病害之一。控制条锈病的最佳策略是种植抗病品种，但可用的有效基因很少。小麦材料H9020-1-6-8-3是先前从小麦基因型7182与华山新麦草（Psathyrostachys huashanica）种间杂交培育出的一个易位系，对中国大多数条形柄锈菌小麦专化型小种具有抗性。为了鉴定该易位系中的抗性基因，将H9020-1-6-8-3与感病基因型铭贤169杂交，并在可控温室条件下，用中国流行的条形柄锈菌小麦专化型小种CYR32和CYR33对亲本及F1、F2和F3代的幼苗进行检测。遗传分析结果表明，H9020-1-6-8-3中的两个单显性基因分别对CYR32和CYR33具有抗性。对CYR33的抗性基因暂命名为YrH9020。利用6个简单序列重复标记，通过在温室中对329株F2植株进行CYR33检测，将该抗性基因定位到小麦2D染色体短臂上。两个最紧密连锁的标记Xgwm261和Xgwm455的遗传距离分别为4.4和5.8厘摩。华山新麦草品系与小麦品系7182、H9020-1-6-8-3和铭贤169之间的侧翼标记的病害评估和多态性检测表明，H9020-1-6-8-3中的抗性基因YrH9020最初来自华山新麦草。该外来的条锈病抗性基因及连锁分子标记对于与其他基因聚合，培育对条锈病具有高水平持久抗性的小麦品种应是有用的。
