found that zinc in wheat grains showed high correlation with protein concentration
when plants were exposed to ozone alone or in combination
with elevated carbon dioxide.
Unlike ozone, carbon dioxide tended to stimulate yields and lead to a dilution of protein and zinc concentrations.
In the case of corn, ozone stress had minor effects on macro-nutrient concentration of K, P and Mg, but the levels of the micro-nutrients Zn, Fe and Cu in corn grains increased with increasing.
ozone concentration