Figure 4.

Penetration frequency of the adapted powdery mildew Erysiphe necator on the Vitaceae species Vitis vinifera, Muscadinia rotundifolia and Cissus rhombifolia following treatment with the following inhibitors: (A) cytochalasin E (CE), 0.25% dimethylsulphoxide (DMSO) or water; (B) brefeldin A (BFA), 0.4% DMSO or water; (C) wortmannin (WM), 0.4% DMSO or water. Successful penetration was scored by the presence/absence of a haustorium. Each data point ± standard deviation is based on three biological replicates (leaves) on which a minimum of 100 germinated conidia were scored. The data shown are representative of the results obtained with at least two independent experiments. Asterisks indicate a significant difference from DMSO controls (P < 0.05; Student's t‐test).