Molecular mapping of QTL for type I Fusarium head blight resistance in two recombinant inbred lines wheat populations

Fusarium head blight (FHB) is a major concern for wheat production and food safety, globally. Resistance to infection (type I resistance) is important for breeding varieties with good FHB resistance. To better understand the genetic architecture underlying type I FHB resistance, quantitative trait loci (QTL) mapping was conducted using two recombinant inbred line populations derived from the crosses Yangmai 4 (YM4)/Yanzhan 1 (YZ1) and Yangmai 5 (YM5)/YZ1. A total of five resistance QTL, including QFhb.yaas-2D, QFhb.yaas-4D, QFhb.yaas-5B, QFhb.yaas-6B, and QFhb.yaas-3A, were detected from these two populations. Except for QFhb.yaas-2D and QFhb.yaas-5B, the resistance effects of all the other QTLs are derived from YM4 or YM5. QFhb.yaas-4D is a common QTL detected both in YM4/YZ1 and YM5/YZ1 populations. QFhb.yaas-2D, QFhb.yaas-4D, and QFhb.yaas-5B were colocalized with known plant height (PH) genes Rht8, Rht-D1, and flowering date (FD) gene Vrn-B1. However, QFhb.yaas-6B and QFhb.yaas-3A were not associated with PH and FD. Kompetitive Allele-Specific PCR markers for QFhb.yaas-6B and QFhb.yaas-3A had been developed and validated in an additional panel of 211 wheat cultivars/lines. The result showed that these two resistance alleles decreased 46.65% of the percentage of diseased spikelets. These results provide valuable information for the fine mapping of QFhb.yaas-6B and QFhb.yaas-3A in the future.