A Pre‐Armed Antioxidant System in RmgGR119 Gene‐Carrying Wheat Genotype GR 119 Exhibits Enhanced Resistance to the Blast Fungus Magnaporthe oryzae Triticum

ABSTRACT Wheat blast, a devastating disease of wheat ( Triticum aestivum ) caused by Magnaporthe oryzae pathotype Triticum (MoT), poses a significant threat to global cereal production and food security. The wheat genotype GR119, which carries the blast resistance gene RmgGR119 , exhibits strong resistance to MoT, but the molecular basis of this defence remains poorly understood. In this study, we employed a comparative approach to dissect the antioxidant defence response of GR119 during MoT infection, using the susceptible wheat cultivar BARI Gom 26 (BG26) as a control. Our results revealed that GR119 experienced significantly lower oxidative stress following inoculation with the pathogen ( p < 0.05), with increases in hydrogen peroxide and malondialdehyde in rachis tissues 48 h post‐inoculation limited to 21% (vs. 30% in BG26) and 43% (vs. 79% in BG26), respectively, compared to the untreated controls. GR119 maintained higher constitutive levels of both enzymatic antioxidants (e.g., superoxide dismutase, catalase and glutathione‐related enzymes) and non‐enzymatic antioxidants (e.g., proline), which were further amplified 1.5–3.0‐fold post‐infection compared to BG26. This enhanced antioxidant capacity correlated with preserved photosynthetic pigments and reduced oxidative damage, underscoring a dual‐layered defence strategy. We demonstrate that RmgGR119 ‐mediated blast resistance is mechanistically tied to a pre‐emptive and pathogen‐inducible antioxidant defence system. These findings provide novel molecular insights into wheat–MoT interactions and position antioxidant pathway engineering as a strategic approach for breeding blast‐resistant wheat.