Radiation-induced translocations with reduced Haynaldia villosa chromatin at the Pm21 locus for powdery mildew resistance in wheat
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Haynaldia villosa Schur. (syn. Dasypyrum villosum Candargy, 2n = 2x = 14, genome VV), a species related to wheat, is highly resistant to powdery mildew. The powdery mildew resistance gene Pm21 from H. villosa was introduced into common wheat by means of a translocation line T6VS·6AL, where the 6VS chromosome arm of H. villosa was joined at the centromere with wheat chromosome arm 6AL. To develop small alien translocations, especially interstitial translocations of small alien chromosome segments, we irradiated mature female gametes of a T6VS·6AL translocation line with gamma rays. More than 20 new translocations and deletions of 6V chromatin were obtained and subsequently used to map Pm21. Pm21 was located in a small region (FL 0.45–0.58) by genomic in situ hybridization, molecular marker analysis, and powdery mildew response. Two homozygous translocation lines with small H. villosa chromosome fragments carrying Pm21 were identified by fluorescence in situ hybridization and molecular marker analysis: an interstitial translocation in which a small fragment of 6VS is inserted into chromosome 4B and a terminal translocation with a small fragment of 6VS inserted into 1A. These small alien translocations are being transferred into an adapted elite wheat background by backcrossing to allow their easy use in breeding programs.
KeywordsTriticum aestivum Irradiation Chromosome translocation Fluorescence in situ hybridization Blumeria graminis
We thank the Jiangsu Academy of Agricultural Sciences for help with the irradiation treatment of plant materials and Professor Bikram Gill for reviewing the manuscript. This research was supported by the National Basic Research Program of China (2009CB118304), the National Natural Science Foundation of China (30871519, 31171540), and the High-Tech Program of China (2006AA10A104, 2011AA10010201, 2011AA100101).
- Cao AZ, Xing LP, Wang XY, Yang XM, Wang W, Sun YL, Qian C, Ni JL, Chen YP, Liu DJ, Wang XE, Chen PD (2011) Serine/threonine kinase gene Stpk-V, a key member of powdery mildew resistance gene Pm21, confers powdery mildew resistance in wheat. Proc Natl Acad Sci USA 108:7727–7732PubMedCrossRefGoogle Scholar
- Chen SW, Chen PD (2010) Development of the specific EST markers for the 6V chromosome short arm of Haynaldia villosa and location of their deletion. J Triticeae Crops 30:789–795Google Scholar
- Chen PD, Zhang SZ, Wang XE, Wang SL, Zhou B, Fen YG, Liu DJ (2002) New wheat variety Nannong 9918 with high yield and powdery mildew resistance (in Chinese). J Nanjing Agric Univ 25:1438–1444Google Scholar
- Chen PD, Liu WX, Yuan JH, Wang XE, Zhou B, Wang SL, Zhang SZ, Feng YG, Yang BJ, Liu GX, Liu DJ, Qi LL, Zhang P, Friebe B, Gill BS (2005) Development and characterization of wheat-Leymus racemosus translocation lines with resistance to Fusarium head blight. Theor Appl Genet 111:941–948PubMedCrossRefGoogle Scholar
- Liu DJ, Chen PD, Pei GZ, Wang YN, Qiu BX, Wang SL (1988) Transfer of Haynaldia villosa chromosomes into Triticum aestivum. In: Miller TE, Koebner RMD (eds) In: Proceedings of the 7th international wheat genet symposium. Cambridge, pp 355–361Google Scholar
- Liu WX, Chen PD, Liu DJ (1999) Development of Tritucum aestivum–Leymus racemosus translocation lines by irradiating adult plants at meiosis. Acta Bot Sin 41:463–467Google Scholar
- Rajaram S, Mann CE, Ortis Ferrara G, Mujeeb-Kazi A (1983) Adaption, stability and high yield potential of certain 1B/1R CIMMYT wheats. In: Sakamoto S (ed) Proceedings of the 6th international wheat genet symposium. Kyoto University, Kyoto, pp 613–621Google Scholar
- Rajaram S, Villareal R, Mujeeb-Kazi A (1990) The global impact of 1B/1R spring wheat. Agronomy abstracts. American Society of Agronomy, Madison, p 105Google Scholar
- Rayburn AL, Gill BS (1986) Molecular identification of the D-genome chromosomes of wheat. J Hered 77:253–255Google Scholar
- Sears ER (1956) The transfer of leaf rust resistance from Aegilops umbellulata to wheat. Brookhaven Symp Biol 9:1–22Google Scholar
- Wang CM, Bie TD, Chen QZ, Cao AZ, Chen PD (2007) Development and application of molecular markers specific to chromosome 6VS of Haynaldia villosa (in Chinese). Acta Agron Sin 33:1595–1600Google Scholar