Characterization of Conferring Powdery Mildew Resistance in Chinese Wheat Landrace Duanganmang.

Wheat powdery mildew, caused by f. sp. , is a devastating disease that threatens yield and quality. Host resistance is considered the most effective and preferred means to control this disease. Wheat landrace Duanganmang (DGM) showed high resistance or near immunity to f. sp. mixture from Henan Province, China. DGM was crossed with highly susceptible Chinese wheat landrace Huixianhong (HXH) and cultivar 'Shimai 15' (SM15) to produce genetic populations. The resistance of DGM to f. sp. isolate E09 was shown to be controlled by a single dominant Mendelian factor, tentatively designated . Marker analysis and 55K single nucleotide polymorphism (SNP) array scanning showed that this gene was positioned in the interval (2.4 cM or 1.61 Mb) flanked by and in the Chinese Spring reference genome. Homology-based cloning and sequence analysis demonstrated that DGM has the identical gene () and gene reported in Fuzhuang 30 (FZ30), conferring and modifying powdery mildew resistance, respectively. However, based on the different reaction patterns to the f. sp. isolate B15 between DGM and FZ30, the authors speculate that DGM may have two tightly linked genes that could not be separated in the current mapping population, one of which is and the other being . Hence, this study provides a valuable resistance resource for improvement of powdery mildew resistance.