Detection of intracellular ROS accumulation in soybean cells treated with fungal culture filtrates. Intracellular ROS were detected by H2DCF-DA staining in control cells (Co, a'), in cells treated with >3 kDa (b'-e') and <3 kDa (f'-i') fractions of wild type Trichoderma (wt Tr, b'and f'), Botrytis (Bo, c'and g'), the coculture of wild type Trichoderma and Botrytis (wt Tr+Bo, d' and h') and the coculture of Trichoderma Δ ech42 mutant and Botrytis (Δ ech42+Bo, e'and i'). For each treatment light (a-i) and fluorescence (a'-i') microscope images of the same field are presented. All images were acquired with the same exposition time gauged to the higher fluorescence emission intensity obtained with the Botrytis <3 kDa fraction. Pictures represent typical examples after 10 min treatment. Bar: 10 μm.