What is red chlorophyll? N> Acer Palmatums ?

Are there general rules like, more sun = more red, more shade = more green? Or is it all in the cultivar? I think the variegated ones need some sun because they don't have the chlorophyll, But, how do maple do it with out the green stuff, like the red ones or what is red chlorophyll ?​

 

The pink/red pigments in purple plants are anthocyanins. Purple plants have ordinary green chlorophyll as well as anthocyanins, which is why they are purple (pink + green), rather than pink. Most if not all plants have anthocyanins, the difference is just that most plants don't have a lot of them (so they are not very conspicuous), whereas purple plants have them in much larger amounts. The amount in a plant is largely determined by genetics (so cultivar choice mages a huge difference), but also to an extent by light levels, with more anthocyanin in leaves in bright sun than in shade.

Anthocyanins do not perform photosynthesis like chlorophyll, but they do have several functions in plants, including as antioxidants, in thermoregulation, and protection from ultraviolet light. Among wild plants, anthocyanin amounts tend to be higher in high altitude mountain species, where they help absorb heat from sunlight, and also help block the more intense UV light at high altitude.

Anthocyanins have also recently been shown to have several benefits in human food, mainly as antioxidants and possibly helping to reduce cancer risks. Good food sources include beetroot, purple fruit, red wine, etc. I don't think purple maple leaves would be worth eating for them, though ;-)

 

Thanks Michael that was very interesting, how about blue berries that must be really high in antioxidants.