There's no such thing as silicon deficiency... wait.... there's no such thing as glucose deficiency... there.. lol
Plants need H,C,O,N,P,K,Ca,Mg,S,Fe,Mn,B,Mo,Zn,Cu. Putting glucose in water will change the tonicity similar to how ions will, but they do not have electric charge, and are not pumped up the xylem like K+ to equalize the tonicity. There's a case to be made that replacing some K+ for glucose during the ripening period will cause the final product to have less K+ in the vacuoles, while keeping tonicity constant, of course I've never heard this argument on RIU yet.
http://scienceinhydroponics.com/2010/09/making-isotonic-solutions-for-draining-preparing-your-own-and-better-clearex.html
Here's the reasoning behind "sweetened flushing solutions" rather than just using water to flush.
Disclaimer: In no way am I saying this means you should flush or use sugars/molasses. I personally don't flush or put sugars in my water. The main reason the writer suggests something like clearex is to prevent soft fruits like tomatoes from bursting from water pressure when rinsing the roots off with RO.