Genetic insights into root disease resistance using the model cereal Brachypodium distachyon

Abstract Fusarium spp. and Gaeumannomyces tritici are fungal root pathogens that cause major yield losses in cereal crops. Management strategies include fungicides, croprotation, and genetic resistance crop applications, but these pathogens continually evolve. Brachypodium distachyon (Bd) acts as a valuable model for temperate cereal crops and is useful for studying root-pathogen interactions. The BrachyTAG program is used in this study to disrupt individual genes in the Bd21 accessions using T-DNA mutagenesis, and the sensitivity of the selected lines were tested to the Fusarium mycotoxin deoxynivalenol (DON) and the root necrosis was monitored during germination. The results showed that disruption of BdAA (annotated accessions 398, 441, and 319) led to distinct resistance to G. tritici and F. culmorum infections and a bZIP transcription factor-encoding gene potentially confers broad-spectrum resistance. These pathogen-specific and general defence genes can be used for breeding and gene editing to enhance cereal crop resilience against root diseases.