NADPH Oxidase Gene, , Plays a Critical Role in Development and Virulence in .

NADPH oxidase is an enzyme that generates reactive oxygen species from oxygen and NADPH and is highly conserved in eukaryotes. In , a series of different Nox enzymes have been identified. NoxA is involved in sexual development and ascospore production and, like NoxB, also contributes to pathogenicity. Both NoxA and NoxB are regulated by the subunit NoxR, whereas NoxC is usually self-regulated by EF-hand motifs found on the enzyme. In this study, we characterized another NADPH oxidase in , . In the deletion mutant, vegetative growth and conidia production were reduced, while sexual development was totally abolished. The deletion mutant also showed reduced resistance to cell wall perturbing agents; cell membrane inhibitors; and osmotic, fungicide, cold, and extracellular oxidative stress, when compared to the wild type. Moreover, in comparison to the wild type, the deletion mutant exhibited reduced virulence against the host plant. The deletion mutant produced less deoxynivalenol than the wild type, and the and gene expression was also downregulated. In conclusion, our findings show that is involved in the survival against various stresses, conidiation, sexual development, and virulence, highlighting this enzyme as a new target to control the disease caused by .