Positional cloning of PmCH1357 reveals the origin and allelic variation of the Pm2 gene for powdery mildew resistance in wheat
Fang Chen,
Haiyan Jia,
Xiaojun Zhang,
Linyi Qiao,
Xin Li,
Jun Zheng,
Huijuan Guo,
Carol Powers,
Liuling Yan,
Zhijian Chang
Affiliations
Fang Chen
College of Life Science, Shanxi University, Taiyuan 030006, Shanxi, China; The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, Shanxi, China
Haiyan Jia
Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK 74078, USA; The Applied Plant Genomics Laboratory of Crop Genomics and Bioinformatics Centre, Nanjing Agricultural University, Nanjing 210095, Jiangsu, China
Xiaojun Zhang
The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, Shanxi, China
Linyi Qiao
The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, Shanxi, China
Xin Li
The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, Shanxi, China
Jun Zheng
Institute of Wheat Research, Shanxi Academy of Agricultural Sciences, Linfen 041000, Shanxi, China
Huijuan Guo
The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, Shanxi, China
Carol Powers
Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK 74078, USA
Liuling Yan
Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK 74078, USA
Zhijian Chang
The Shanxi Province Key Laboratory of Crop Genetics and Gene Improvement, Institute of Crop Science, Shanxi Academy of Agricultural Sciences, Taiyuan 030031, Shanxi, China; Corresponding author.
Powdery mildew, caused by the biotrophic fungus Blumeria graminis f. sp. tritici (Bgt), is a prevalent disease in common wheat (Triticum aestivum L.) and causes serious yield losses worldwide. We used a map-based approach to clone the major broad-spectrum powdery mildew resistance gene PmCH1357 from wheat breeding line CH1357. PmCH1357 was mapped to a 526 kb region containing only TraesCS5D01G044600. The TraesCS5D01G044600 sequence of the susceptibility allele in Taichung 29 (TC29) was identical to that in Chinese Spring, whereas the sequence of the resistance allele in CH1357 was identical to Pm2a previously cloned from the germplasm Ulka/*8Cc. The susceptibility allele in TC29 contained a 7 bp deletion in exon 1, resulting in loss of 856 of the 1277 amino acids in the predicted nucleotide-binding domain leucine-rich repeat containing Pm2a protein. PmCH1357/Pm2a sequence was also isolated from the Chinese wheat landraces and cultivars that were previously reported to possess the resistance gene Pm2b, Pm2c, PmLX66, or PmND399. The PmCH1357/Pm2a resistance allele was present in 10 of 495 accessions in core germplasm and contemporary cultivars from China and the USA. A newly developed diagnostic marker for the 7 bp InDel in the resistance gene can be used to eliminate the susceptibility allele in wheat breeding programs. Keywords: Map-based cloning, Natural variation, Bgt isolate E09, Triticum aestivum, Molecular breeding
