Figure 3.

Peroxidases involved in the oxidative stress responses in Fusarium graminearum. (A) Oxidative stress sensitivity of F. graminearum strains. The mycelial growth of four peroxidase deletion mutants was evaluated on complete medium (CM) with and without supplementation with 10 mm H₂O₂. Photographs were taken 5 days after inoculation. (B) Peroxidase enzyme activities of the F. graminearum strains. (C) Hydrogen peroxide detection in mycelia of the F. graminearum strains. (D) Virulence on wheat heads. The centre spikelet of each wheat head was injected with 10 µL of a conidial suspension, and photographs were taken 21 days after inoculation. Arrowheads indicate the inoculated spikelets. ‘Mock’ indicates wheat heads that were mock inoculated with 0.01% Tween 20. (E) Total trichothecene production by the F. graminearum strains. Each strain was grown in minimal medium containing 5 mM agmatine (MMA) for 7 days. Trichothecenes were analysed by gas chromatography‐mass spectrometry (GC‐MS) and quantified based on the biomass of each strain. (F) Transcript levels of TRI5 and TRI6 in the wild‐type (WT) and fca7 deletion mutant strains. The transcript levels were analysed by quantitative real‐time polymerase chain reaction (qRT‐PCR) 4 days after inoculation in MMA. Asterisk indicates significant difference: P < 0.01, Tukey's test.