Figure 7.

Silver treatment induces anthocyanin production and reduces disease progression in maize. (A) Untreated control plants showed unimpaired growth with little anthocyanin formation in the stem area. (B) Plants treated with 0.412 g AgNO₃ per litre of soil showed reduced growth and increased anthocyanin production in the stems and basal parts of the leaves. Note that the plants were photographed at the same magnification in (A) and (B). (C) Disease symptoms and disease rating (DI, disease index) of untreated, but infected, control plants after 14 days. (D) Disease symptoms and disease rating of infected and AgNO₃ (0.412 g/L soil)‐treated plants after 14 days. Plants were infected as 7‐day‐old seedlings with a mating‐compatible culture of wt strains at 5 × 10⁶ cells/mL. AgNO₃ was added to the soil at the beginning of the experiment. The experiment was repeated three times and with a range of additional silver concentrations (Fig. S3). Standard deviations are shown. **Statistically significant differences at P < 0.01. The plant symptoms were scored as described in Fig. 5.