For all experiments, leaf discs were inoculated with conidia of
the B. lactucae strain Bl:18. In experiment A, inoculation was performed
by spraying leaf discs with a freshly prepared conidia suspension
of 0.4 105 conidia mL1 (total volume = 2 mL inoculum
per Petri dish). To promote the success of inoculation, discs were
kept dark after inoculation for 24 h. In experiment B, the concentration
of the conidia suspension was 1 105 conidia mL1 and
dark period after inoculation was reduced to 12 h.