2012 Annual Report
Fusarium head blight (FHB) is an important disease that attacks the heads and reduces both yield and quality of wheat. New sources of genetic resistance are being sought to improve the resistance of hard winter wheat varieties. Two new genetic mapping populations were constructed from crosses between two resistant Chinese landraces, Baisanyuhuang and Huangcando, and Jagger (a highly susceptible hard red winter wheat parent). The populations were scored for FHB resistance under greenhouse conditions and then the resistance genes were mapped using molecular markers. The results showed that both Chinese varieties have the known resistance gene Fhb1 on wheat chromosome arm 3BS. Additional genes for resistance were identified near the centromere of chromosome 3BS in Baisanyuhuang and on chromosome arm 3AS in Huangcando. We are currently evaluating whether these resistance genes will be valuable additions to our defenses against FHB.
In a marker-assisted selection project, Fhb1 and several other FHB resistance genes were transferred into Jagger and Overley (cultivars from Kansas) and Overland (cultivar from Nebraska). About 300 lines were selected for resistance by FHB testing in two greenhouse seasons. These materials will be released to breeders after final marker confirmation that they carry the desired genes. Previously, we had produced backcross lines of cultivar Wesley carrying Fhb1, which we distributed to regional breeding programs. New crosses were made with 11 elite breeding lines from Oklahoma, Kansas, North Dakota, South Dakota, and Nebraska to transfer Fhb1 to additional breeding lines.