Rapid discovery and validation of novel mutations to enhance disease resistance in wheat via a Mut-Ed approach

About This Grant

Fungal pathogens pose a significant threat to crop plants and consequently, food safety and security. Previously, several years of rigorous testing of a chemically mutagenized population in field and greenhouse conditions identified two unique variations in an elite wheat variety to provide resistance to Fusarium graminearum, the causal pathogen of Fusarium Head Blight (FHB) disease. This project will identify and validate the genomic variations responsible for resistance to the fungal pathogen. To corroborate findings, the project will recreate the variations in another wheat variety using gene editing and study the effects on plant performance. The long-term goal of the project is to investigate and implement novel resistance strategies in plants to combat challenging fungal pathogens that utilize a variety of pathogenic lifestyles. To broaden the impact of the work, the project team will share seeds of the resistant wheat lines developed in the project with interested breeders and geneticists for field testing and potential deployment in crop varieties. The project will train high school students, undergraduate students, PhD students, and postdoctoral scientists with the next generation of tools and technologies in plant biotechnology research and their application to ensure food security. This project builds upon a multi-year, rigorous genome-wide screen in wheat to select independent mutations conferring resistance against the hemibiotrophic fungal pathogen Fusarium graminearum. The specific aims of this project are: 1) Validation and assessment of FHB resistance mutations on chromosome 2D, and 2) Fine-mapping and validation of the causal mutation for resistance on chromosome 7A. Mutation mapping populations were developed and phenotyped, followed by whole genome sequencing of the resistant bulks to map and shortlist independent candidate mutations on the short arms of chromosomes 2D and 7A. Multiplex editing will be done to validate the mutations underlying the resistant phenotype. The confirmed mutation will be further validated in another variety, and the fitness cost, if any, of the mutation on the plants will be determined by a thorough assessment of plant health and performance. The independent mutations identified in the project will provide new targets for engineering resistance against the difficult necrotrophic and hemibiotrophic pathogens in crop plants. The project team will share the seeds of edited wheat generated in the project with interested breeders and geneticists for their field testing and deployment. Research findings and knowledge about tools, technologies, and applications of plant science research will be disseminated to the general public. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.