Powdery mildew, caused by *Blumeria graminis* f. sp. *tritici* (Bgt), is a devastating wheat disease. This study reports the map-based cloning of the powdery mildew resistance gene *Pm24* from the Chinese wheat landrace Hulutou. *Pm24* encodes a tandem kinase protein (WTK3) with kinase-pseudokinase domains. A rare 6-bp deletion, resulting in a two-amino acid deletion (lysine-glycine) in the kinase I domain, is crucial for resistance. Transgenic assays and mutant analyses confirmed WTK3's role and the specificity of the two-amino-acid deletion in conferring resistance.

Ping Lu, Li Guo, Zhenzhong Wang, Beibei Li, Jing Li, Yahui Li, Dan Qiu, Wenqi Shi, Lijun Yang, Ning Wang, Guanghao Guo, Jingzhong Xie, Qiuhong Wu, Yongxing Chen, Miaomiao Li, Huaizhi Zhang, Lingli Dong, Panpan Zhang, Keyu Zhu, Dazhao Yu, Yan Zhang, Karin R. Deal, Naxin Huo, Cuimin Liu, Ming-Cheng Luo, Jan Dvorak, Yong Qiang Gu, Hongjie Li, Zhiyong Liu