Fig. 4

Development of Phyllachora maydis stromata on corn leaves in four corn (Zea mays L.) hybrids (H1 to H4; Table 1) in growth chamber or greenhouse conditions after using the new inoculation method. Stromata of P. maydis developed on 100% of the inoculated plants in all experiments when spores were collected from field-infected plants located in the greenhouse (experiments 1 to 3) or field-infected green leaves stored at -20 ºC for 5 months (experiment 4). Note that the scale on the y-axis varies between experiments. A. Number of P. maydis stromata per leaf 26 dai in a growth chamber and greenhouse. B. Number of P. maydis stromata 19 dai in a growth chamber and greenhouse. C and D. Number of P. maydis stromata per leaf 19 dai in a greenhouse. “N” equals the total number of stromata of P. maydis counted from each hybrid in the given experiment. Different letters in B and C (experiments 2 and 4) denote statistical differences as determined by Tukey’s Honestly Significant Difference (P < 0.05). In A and D (experiments 1 and 4), the development of P. maydis was not statistically different (P > 0.05)