Marker-assisted selection to pyramid Fusarium head blight resistance loci Fhb1 and Fhb2 in the high-quality soft wheat cultivar Yangmai 15

Fusarium head blight (FHB) is one of the most detrimental wheat diseases which greatly decreases the yield and grain quality, especially in the middle and lower reaches of the Yangtze River of China. Fhb1 and Fhb2 are two major resistance loci against Fusarium graminearum. Yangmai 15 (YM15) is one of the most popular varieties in the middle and lower reaches of the Yangtze River, and it has good weak gluten characters but poor resistance to FHB. Here we used Fhb1 and Fhb2 to improve the FHB resistance of YM15 by a molecular marker-assisted selection (MAS) backcrossing strategy. The selection of agronomic traits was performed for each generation. We successfully selected seven introgressed lines which carry homozygous Fhb1 and Fhb2 with significantly higher FHB resistance than the recurrent parent YM15. Three of the introgressed lines had agronomic and quality characters that were similar to YM15. This study demonstrates that the pyramiding of Fhb1 and Fhb2 could significantly improve the FHB resistance in wheat using the MAS approach.