In the first crop, the leaf SOD activitywas greater in the plants grown
in the soil supplementedwith 30 mg Zn kg−1, although the activitywas
smaller when the greatest dose of Zn was used (Fig. 4). Although low
POD activity was observed, this parameter was greater when Zn was
not added and smaller when 90 and 270 mg Zn kg−1 were added.
However, no statistically significant differences occurred between the
SOD and POD activities in the second crop. When comparing both
maize crops, the SOD activity was greater than the POD activity in the
first crop but smaller in the second crop.