adding rye to whole wheat starter

My understanding is there is none.  In an active starter, the yeast and bacteria you need should be present and thriving.  Adding rye flour just adds more.  There is no benefit flavor-wise.  The flavor in the bread comes from the fermentation stage.

I am of the notion that adding different flours to a starter will change the flavor of the bread it produces.  A white flour starter makes bread that changes quite dramatically when the starter is converted to a  rye one.  The rye starter makes bread taste more earthy and has more sour according to my taste buds but they are old and maybe not working as well as younger ones:-)  Sprouted grains make the taste difference even more dramatic.

Happy baking 

that feeding a starter mixed flours (white, whole wheat, rye, etc.) on a regular basis equips it to deal with the varying flours in the breads made with the starter.  I've no way to verify that notion but I know that there are folks who maintain a blend of 70% white, 20% whole wheat, and 10% rye flour specifically for feeding their starters. 

My starter is more of a mongrel that gets fed whatever is closest to hand, although I do like to give it some rye each time if I think to.

Paul

I keep a rye and wheat starter.. and they taste very different. I vary my loaves by using either of them or changing the amounts of both depending on what I am trying to achieve.