Researchers in China have identified a new genetic resistance locus against Fusarium head blight in Elymus repens, a wild relative of wheat, and successfully transferred the trait into wheat hybrids, a development that could support future breeding efforts targeting one of the cereal industry’s most damaging diseases.
The study focused on transferring Fusarium head blight, or FHB, resistance genes from Elymus repens, commonly known as coach grass, into cultivated wheat through hybridization.
FHB is a fungal disease that reduces grain yield and contaminates grain with mycotoxins harmful to humans and livestock. Infected grain often must be destroyed, making the disease a major economic challenge for wheat producers worldwide.
“Both research and breeding practice have shown that developing and deploying resistant wheat cultivars is the fundamental solution to FHB,” said study author Fei Wang. “However, current efforts are limited by a scarcity of major resistance sources, narrow genetic backgrounds and inefficient use of resistance genes.”
New Resistance Locus Identified
The research team, led by Yinghui Li and Houyang Kang, identified a previously undocumented resistance locus after hybridizing coach grass with cultivated wheat.
According to the study, hybrid genotypes carrying the resistance genes showed a 69% reduction in diseased spikelets under greenhouse conditions compared to control wheat lines. Field trials showed a 60% reduction in disease symptoms.
Researchers also reported that the hybrids lacked genetic markers associated with previously identified alien FHB resistance genes, indicating the resistance source represents a novel genetic locus.
Researchers said the findings expand the pool of available resistance sources that breeders can use in wheat improvement programs.
Implications for Wheat Breeding
The researchers said the work could help address long-standing limitations in FHB resistance breeding, particularly the narrow genetic base currently available for commercial wheat improvement.
“We believe this work is of practical importance for accelerating the breeding of resistant, high-yielding wheat varieties and breaking the bottleneck in FHB resistance breeding,” Li said.
Because Elymus repens is genetically related to cultivated wheat, the species can be crossed with wheat to transfer useful agronomic traits into breeding lines.
For wheat breeders and cereal researchers, the discovery may provide an additional resistance source capable of improving disease tolerance while supporting yield stability and grain quality.
The study was conducted by researchers from the State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China at Sichuan Agricultural University in Chengdu, China.
Source: Journal of Experimental Botany, "Identification of a novel Fusarium head blight resistance locus Fhb.Er-1StL from Elymus repens introgressed into wheat"