Can you use your white flour starter for other breads like rye, whole wheat? Instead of having several different starters. how does it effec the outcome?
Think of your white starter as a mother starter.
When you want to make rye bread, make a rye starter using some of your mother starter.
How do you make a rye starter? Rye flour + water + a bit of mother starter.
Ditto whole wheat, durum, buckwheat, etc.
When you want to make whole wheat bread, make a whole wheat starter using some of your mother starter..
How do you make a whole wheat starter? Whole wheat flour + water + a bit of mother starter.
Does the same hold true for whole grain flour?
If I needed to make a rye bread and used white starter rather than wait to develope a rye starter would the taste really be that different
It depends on how much white starter you use.
If the recipe calls for 10 oz of rye starter and you use 10 oz of white starter, there will be a difference in taste, structure, bulk fermentation, etc.
Whether that's discernable in the final product depends on the person eating it. I would know the difference, but would most? Probably not.
People have been doing this for years. A lot of TFL members, myself included, will tailor their starters to match the flour contained in their loaves. Your best bet, for cost and simplicity's sake, is to keep a single starter and then build a starter for each loaf with a seed from from the original. By the time your new starter is in its third stage, you'll effectively have a rye, white, or whole wheat starter depending on what you built from. The key is to begin very small, about 50 g or so. Any leftover stater from the third stage can be frozen for use as pate fermentee or dryed to keep as a backup in case your starter fails.
There are archived threads in the forums that discuss this subject more thoroughly than I can here.
I use AP flour to feed my starter because it is cheapest and most readily available. I make 100% whole wheat bread using it with no problems. I have used the AP starter for low percentage (25%rye/75%WW) rye bread with no problems. I have made other starters from this starter for special recipes, such as high percentage rye. It works great. I guess I'm not a purist.
Have delicious fun!