Symptom rating and in planta growth of U. maydis hyphae. (A) Symptom rating of the U. maydis strain SG200Δcce1 in comparison to the progenitor strain SG200 and three individual SG200Δcce1‐cce1‐3xHA complementation strains 12 days post infection (dpi). Mean and standard deviation of relative counts from four replicates are displayed. For clarity, only positive error bars are shown. n = number of plants scored. Significant differences between the strains are indicated by a, b, c. p‐values calculated by Fisher’s exact test, MTC by Benjamini‐Hochberg algorithm, α = 0.05. (B) Seven‐day‐old Z. mays seedlings were infected with U. maydis strains, leaves were harvested two days post infection (dpi). Fungal hyphae were visualized by WGA‐AF488 (green), plant cell walls stained with propidium iodide, and observed via confocal microscopy. Maximum projections of Z‐stacks are shown; scale bar = 50 μm.