A new experimental study has identified a novel genetic locus in a common agricultural weed, Elymus repens, that provides significant resistance to the destructive fungal disease Fusarium Head Blight (FHB) and has now been successfully transferred into wheat to produce FHB resistant hybrids.
FHB is a virulent fungal disease that poses a serious threat to global food security and is regarded as one of the world's most economically harmful cereal diseases. FHB reduces grain yield and produces mycotoxins that cause gastrointestinal issues in humans and livestock, requiring infected crops to be destroyed.
E. repens, more widely known as coach grass or common coach, is a wild relative of cultivated wheat, allowing for the two species to breed together and create genetic hybrids.
"Both research and breeding practice have shown that developing and deploying resistant wheat cultivars is the fundamental solution to FHB," says 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."
Dr Yinghui Li and Houyang Kang's research team's new study, published in the Journal of Experimental Botany, outlines how they successfully hybridised E. repens and cultivated wheat to transfer FHB-resistant genes from E. repens into the wheat.
When testing for the presence of FHB from deliberately infected plants, hybrid genotypes containing the resistance genes, labelled as 1StL, showed a 69% reduction in diseased plant spikelets under greenhouse conditions compared to the control wheat, and a 60% reduction under field conditions.
The researchers found no presence of genetic markers from previously identified alien FHB resistance genes in the hybrids, indicating that 1StL carries a novel resistance locus, which the team has named Fhb.Er‑1StL.
Notably, this is the third resistance locus that Dr Yinghui Li and Houyang Kang group has identified from Elymus repens, following their earlier discoveries of QFhb.Er‑7StL and Fhb.Er‑3StS. The new locus represents an additional, valuable source of resistance that can now be used in wheat breeding.
"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," says Dr Yinghui Li.
This study was conducted by researchers from State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Sichuan and Agricultural University, Chengdu, China.
The Journal of Experimental Botany is a partially open access journal published on behalf of the Society for Experimental Biology by Oxford University Press. The aim of the Journal of Experimental Botany is to publish papers that advance our understanding of plant biology.
