Figure 8.18: Cytoplasmic Inheritance In four o’clock plants, leaf color is inherited through the female plant only. In the parent plant with some white leaves, the white leaf color is caused by a chloroplast mutation that occurred during the life of the plant; the leaves that formed before the mutation occurred are green. When this plant is used as a pollen donor in a cross with an all green plant, the offspring are all green. But when the same plant is used as an egg donor, the offspring inherit the mutation cytoplasmically and are entirely white.