Studies on Petunia. VI. The Origin and Distribution of Color in the Anther and in the Pollen of Petunia

Abstract
Color in the anther first occurs in the domes of sterile tissue enclosed by the 4 crescent shaped microsporangia. The first brightly colored cell sap to appear in the anther is not a true anthocyanin. The red, blue, or purple color of the mature anthers and of the pollen grains is due to the presence of both a blue and a red anthocyanin, the various shades of color depending on the relative amounts of these 2 antho-cyanins together with the yellow pigment present. The color of the pollen may be much strengthened, in mass, by the presence of certain "color bodies." Both anthers and pollen always carry a foundation color of yellow. A portion of this yellow pigment may be extracted by water; another portion by alcohol; but the larger portion remains insoluble in all chemicals tried. This may account for the yellow color of spores and pollen found buried in coal fields.