Neu Christina, Keller Beat, Feuillet Catherine
Institute of Plant Biology, University of Zürich, Zollikerstrasse 107, CH-8008 Zürich, Switzerland.
Mol Plant Microbe Interact. 2003 Jul;16(7):626-33. doi: 10.1094/MPMI.2003.16.7.626.
Cultivated barley, Hordeum vulgare L., is considered to be a nonhost or intermediate host species for the wheat leaf rust fungus Puccinia triticina. Here, we have investigated, at the microscopic and molecular levels, the reaction of barley cultivars to wheat leaf rust infection. In the nonhost resistant cultivar Cebada Capa, abortion of fungal growth occurred at both pre- and posthaustorial stages, suggesting that defense genes are expressed throughout the development of the inappropriate fungus during the nonhost resistance reaction. In the two barley lines L94 and Bowman, a low level of prehaustorial resistance to P. triticina was observed and susceptibility was comparable to that of wheat control plants. Suppression subtractive hybridization was used to identify genes that are differentially expressed during the nonhost resistance reaction in Cebada Capa as well as during the successful establishment of the inappropriate wheat leaf rust fungus in L94. Northern analysis indicated that two candidate genes, including a barley ortholog of the rice resistance gene Xa21, are putatively involved in nonhost and non-race-specific resistance reactions. In addition, a new gene that is specifically induced during the successful development of the inappropriate fungus P. triticina in barley has been identified.
栽培大麦（Hordeum vulgare L.）被认为是小麦叶锈病菌（Puccinia triticina）的非寄主或中间寄主物种。在此，我们在微观和分子水平上研究了大麦品种对小麦叶锈病感染的反应。在非寄主抗性品种Cebada Capa中，真菌生长在吸器前和吸器后阶段均出现败育，这表明在非寄主抗性反应过程中，防御基因在不合适的真菌整个发育过程中都有表达。在两个大麦品系L94和Bowman中，观察到对小麦叶锈菌有低水平的吸器前抗性，其感病性与小麦对照植株相当。抑制性消减杂交被用于鉴定在Cebada Capa的非寄主抗性反应期间以及在L94中不合适的小麦叶锈菌成功定殖期间差异表达的基因。Northern分析表明，两个候选基因，包括水稻抗性基因Xa21的大麦直系同源基因，可能参与非寄主和非小种特异性抗性反应。此外，还鉴定出一个在大麦中不合适的真菌小麦叶锈菌成功发育期间特异性诱导的新基因。
