Yeah I should've been more clear about that. I'm currently getting my BS in physics so I'm more than aware of how energy correlates with the frequency/wavelength of electromagnetic radiation.

I'm under the assumption that there is some key information I'm missing regarding how energy is transferred to water from the electromagnetic radiation that makes green light carry more effective or usable energy for breaking those intramolecular bonds. Perhaps it's the sepcific size of the wavelength? I know that often times when an objects size matches the wavelength passing through them some interesting things can happen though I don't know details on this subject so I can't be certain here.

In the case of plants the green light only carries more effective energy because the sun releases so much of it. Blue light carries more energy but green light is released so much more that it's share of the percentage of total energy released by the sun is much greater. So when sunlight fluctuates for one reason or another it's easier for the plant to regulate it's own energy if it blocks out some of that green light.

I'll amend that in my original comment