DESIGNING INNOVATIVE STRATEGIES FOR SUSTAINABLE MANAGEMENT OF FUSARIUM HEAD BLIGHT IN WHEAT

Abstract

Fusarium Head Blight (FHB), primarily caused by the fungal pathogen Fusarium graminearum, is one of the most economically damaging diseases of wheat worldwide. The overall goal of this dissertation is to establish long-term sustainable strategies for effective and reliable FHB management by leveraging innovative genetic approaches, shortening the generation time to develop FHB-resistant cultivars, and examining the effectiveness of newly released fungicides. While traditional resistance breeding has focused on incorporating resistance (R) genes from diverse germplasm, this research adopts a innovative approach by targeting susceptibility (S) factors to confer resistance. Using MutMap analysis, a key 4.6 Mb region associated with FHB susceptibility was identified on the short arm of chromosome 2D in the widely cultivated wheat variety ‘Jagger.’ Additionally, a conserved FHB-associated region was discovered on the short arm of chromosome 7A in the Chinese Spring background using recombination-independent approaches. Comparative genomic analysis led to the identification and characterization of DMR6 as a susceptibility factor in durum wheat. To address the challenge of the long breeding pipeline in developing FHB resistant cultivars, screening protocol of germplasm under accelerated growth conditions was optimized. Working on the chemical control options for FHB, the fungicide efficacy of a newly released fungicide, Sphaerex, was tested. Collectively, this research provides a robust foundation for developing FHB-resilient wheat cultivars through integrated, innovative, and sustainable approaches.