Registration of WGC002 spring wheat containing wild grass-derived Fusarium head blight resistance gene Fhb7The2

Abstract

The USDA-ARS and North Dakota State University Agricultural Experiment Station jointly released the Fusarium head blight (FHB)-resistant spring wheat (Triticum aestivum L.) germplasm WGC002 (Reg. no. GP-1089, PI 702949) in May 2023. WGC002 is a wheat-Thinopyrum elongatum 7B-7E translocation line, designated 7BS·7BL-7EL, with the wheat chromosome 7BL terminal region replaced by the homoeologous counterpart of the Th. elongatum chromosome 7EL that contains the novel FHB resistance gene Fhb7^The2. WGC002 was developed from the Chinese Spring (CS) wheat-Th. elongatum disomic substitution line DS 7E(7B) using our genomics-enabled chromosome engineering pipeline. The pedigree of WGC002 is DS 7E(7B)/2*CS ph1b mutant//DS 7E(7B). WGC002 has consistently exhibited resistance to FHB in inoculations of greenhouse grown plants. WGC002 does not contain the yellow flour pigment gene in the Fhb7^The2 haplotype present on the terminal 7EL segment of the 7BS·7BL-7EL translocation and has not exhibited any obvious linkage drag on the 7EL segment. Therefore, WGC002 is ready for immediate use in wheat breeding. One sequence-tagged site (STS) and two polymerase chain reaction allelic competitive extension markers were developed specifically for Fhb7^The2 and validated in different wheat genotypes. They are highly diagnostic for Fhb7^The2 and extremely useful in marker-assisted introgression of Fhb7^The2 in wheat breeding. In summary, WGC002 is a new wild grass-derived FHB-resistant spring wheat germplasm with diagnostic DNA markers available to conduct marker-assisted selection of Fhb7^The2, that will enhance and diversify FHB resistance of wheat.