lets think about this logically, in the photosynthesis equation given a cuople of pages back, there is only CO2 and H2O and energy need to photsynthesize. the plant then uses the sugars produced from the photosynthesis to grow. what if that isn't the only process used to create useful sugars for the plant? If all you need is carbon, oxygen and hydrogen, coudn't there be another process that uses O2, carbon and H2O to photosynthesize?
This may be implausable, it's been a while since I took chemistry.
However, the empirical data is that plants do better with more O2 provided to the roots. Now knowing this, regardless of knowing HOW the plant uses the oxygen. Is it not concievable (at least as a grounds for some experimentation) that a plant which has CO2 available to the root system, if not taking the CO2 directly to the upward growth, could bond the CO2 to something which will take the Carbon atom, and result in O2 as a byproduct? This very well could be one of the myriad of processes that a plant undergoes, just happening to reult in useful O2. Nature's kind of good at multi-tasking like that.
On a side note, what are the results of H2O2 being added to the soil (or hydro/aero solution)? Could the "free" O atom be neccesary (or at least useful) for some process in the roots?
Basically, I don't think there's enough data either way to prove or disprove this theory. Fourtunately, we don't absolutely need to know all the internal working of our plants. We only need to know what works. I think until we se some tests and results, we really can't solve this question. When I get my new grow room up and running, I might do a sideXsideXside comparison of CO2,H2O2, and plain H2O added to the soil.
Oh, and the plants are diong pretty good, budding seems to become along alot better than my last grow, and so far I haven't seen any signs of problems from the roots' close quarters. Hopefully pics in the next couple of days. I've got a friends digi for a few days so I'll try and take some good pics whlie I got it.
Good luck.