B, Effect of the deletion of hoxA or hoxB on red-light induction of the ccgA gene. A. alternata strains were grown for 36 h at 28°C. Samples were illuminated for 1 h in red light while controls were kept in the dark. The amount of ccgA transcript was quantified by qRT-PCR analyses with the histone 2B gene as housekeeping gene. Error bars represent the standard deviation (n = 3). 