I don't think that CO2 is the limiting reactant in plant growth. If I remember my bio/chem right, plants use sunlight to produce sugars using the carbon from CO

I don't think that CO2 is the limiting reactant in plant growth. If I remember my bio/chem right, plants use sunlight to produce sugars using the carbon from CO2. The sugars act as an energy store, and the energy can later be reclaimed by doing the inverse reaction, which involves taking O2 and producing CO2. Providing more CO2 would increase the theoretical capacity for them to store energy, however CO2 is abundant and it would not help with the limiting reactant, sunlight.