Molecular marker assisted identification of Pm genes involved in the powdery mildew resistant wheat cultivars (lines).

The Pm genes contained in wheat cultivars (lines) developed by Cytogenetics Institute of Nanjing Agricultural University in corporation with Lixiahe Agricultural Research Institute of Jiangsu Province and those from other sources were identified using RFLP markers tightly linked to Pm2 and Pm4a genes. The Pm genes identified in most of the tested materials by molecular markers were in accordance with these by pedigree deduction and analysis of resistance spectrum. But, the statements previously made about “Baimian No.3”, “Kenguia No.1” and “Zhengzhou 831” containing “Pm2x”, “KG” (6A) and Pm2+6 respectively, were not coincided with the results based on the molecular marker analysis which showed that all above mentioned three cultivars contain Pm4 gene, instead of Pm2 gene. The results were also in agreement with that from resistance spectrum analysis. Two cultivars used as Pm6 differential hosts Timgalen and CI12632/8Cc introduced from IWWPMN, in which the resistance was degraded, were confirmed the Pm6 gene had been lost by RFLP analysis.