Strategies for fine mapping QTLs for crown rot resistance in wheats

Abstract

[Introduction]: Crown rot (causal organism Fusarium pseudograminearum) is of great significance to wheat yields within Australia, with losses estimated at $56M per annum. As part of the Australian Winter Cereals Molecular Marker Project (AWCMMP), our group has been responsible for identifying molecular markers for quantitative trait loci (QTLs) that contribute to crown rot resistance. Using a number of double-haploid mapping populations, we have identified genomic regions that are associated with resistance. While the markers flanking these QTLs will be of use to breeding programs for marker assisted selection, how these QTLs function in conferring resistance is not understood. This apper outlines QTLs identified in two double-haploid populations, and discusses the use of resistance gene analog (RGA) markers and rice-wheat synteny as strategies that may be helpful for understanding the underlying mechanisms for resistance.