Fusarium graminearum is the causative agent of Fusarium head blight (FHB)
in hexaploidy wheat (Triticum aestivum) which substantially reduces the
crop yields and quality. Yield loss is mainly caused by the kernel size
reduction and sterility of infected spikelets while the quality loss is caused
by the presence of mycotoxins primarily deoxynivalenol (DON). Development of
disease resistant crops by deploying host resistance genes is one of the
effective approaches for the FHB management. Many genetic loci were reported to
contribute to resistance to FHB resistance, including Fhb1. Fhb7, a major QTL
for FHB resistance in wheat, has been introgressed into soft red winter wheat
(SRWW) at Purdue University. Being an exotic QTL, Fhb7 is associated with the
linkage drag impacting agronomic and end-use quality performances. This poster
explains the breeding scheme for introducing and pyramiding Fhb7 into breeding
materials that already had Fhb1. In the final step of product development, we
tested 57 SRWW lines which were advanced through the breeding programs to
homozygosity by using PCR diagnosis markers, which revealed that 9 out of 57
showed the presence of both Fhb7 and Fhb1. The expectation is that the stack of
Fhb1-Fhb7 offers additional genetic protection to SRWW against FHB disease.
Fhb7-positive lines showed average agronomic and superior FHB performance. In
particular, they expressed low severity and DON content. The release of
selected wheat breeding lines with the information of multiple genetic markers
linked FHB resistant QTL will be a useful resource for our national USWBSI
breeding community for incorporation of this novel genetic resistance into
their breeding materials.