What do red petunias and lemons have in common?
They share a cell mechanism that regulates acid.
Ronald Koes at Univ. of Amsterdam discovered that red petunias have a vacuole proton pump that concentrates acid in their flower cells. Without the acid, those petunias would be blue.
He then examined DNA in a variety of citrus fruits, from sweet to very sour, and found that the sour ones have the same cell mechanism.
This discovery gives fruit and flower breeders a DNA marker for achieving desired colors and flavors.
Are red petunia flowers sour? … I’m not going to taste them to find out.
Read more about this discovery in Science Magazine.
(photos from Wikimedia Commons)