DNA markers for resistance to common bunt in ‘McKenzie’ wheat.

Common bunt, caused byTilletia tritici(Bjerk.) G. Wint. in Rabenh. andT. laevisKϋhn in Rabenh., is an economically important disease of wheat (Triticum aestivumL.) worldwide. The hexaploid wheat cultivar ‘McKenzie’ possesses effective resistance against known races of common bunt in western Canada. Understanding the nature of this resistance through DNA marker mapping will be useful for breeding. Disease reaction toT. triticirace T19 andT. laevisrace L16 from field tests was analysed with simple sequence repeat markers for 174 doubled haploid lines using interval mapping. MarkersXgwm573andXwmc17, located on wheat chromosome 7B, were strongly associated with the resistance. The quantitative trait locus was designatedQCbt.spa-7B.1. The markers were validated on two other populations in which ‘McKenzie’ was in the parentage. The markers will be useful in breeding as a tool for selecting for common bunt resistance from ‘McKenzie’ and will assist in identifying the resistance among potential new sources. [ABSTRACT FROM AUTHOR]