云南省小麦品种(系)苗期抗秆锈性评价及3个重要抗病基因的分子检测

正小麦秆锈病是严重影响小麦产量的病害之一。小麦秆锈菌新小种Ug99及其变异菌株的出现~(1]),随后在肯尼亚和埃塞俄比亚引起的流行,引起了全球对小麦抗秆锈性的再次关注~(2,3])。云南省地处中国西南边境,历史上是中国小麦秆锈菌主要越冬区,为小麦秆锈病的流行提供初菌源。近几年我们对小麦秆锈病的调查研究发现,即使在全国各地几乎见不到该病的情况下,云南省每年均有小麦秆锈

Seedling resistance appraisal and detection of three important genes conferring resistance to stem rust in wheat cultivars or lines from Yunnan Province

Yunnan Province, the Southwest border of China, is the key initial inoculum source region for the spread and epidemic outbreaks of wheat stem rust. Revealing genes conferring stem rust resistance in wheat cultivars is an important theoretical base for the prevention and control of the disease. Six races of Puccinia graminis f. sp. tritici and three molecular markers, specific for detection of stem rust resistance genes Sr31, Sr32 or Sr38, respectively were used for analyzing the resistance at wheat seedling stage and for detecting resistance genes in 116 wheat cultivars (lines) from Yunnan Province. The result indicated that eighty cultivars showed different resistance to all the tested races, accounting for 69.0% of the tested cultivars (lines). Molecular detection result showed 43 cultivars carrying Sr31, 10 cultivars carrying Sr38, accounted for 37.1% and 8.6% of the tested cultivars or lines, respectively. Only wheat cultivar 91E001 was detected to contain Sr32 that is resistant to Ug99. These results indicate that the resistance of cultivars in Yunnan to wheat stem rust is in a moderate level. Sr31 is present in relatively more cultivars, while Sr38 with excellent resistance to Chinese Pgt gene is relatively fewer. Sr32 conferring resistance to Ug99 is rarely present in Yunnan cultivars.