A corn differs from a bulb in that

A corn differs from a bulb in that its stem is the main food storage organ. In corn plants, the stem is modified to form the edible kernel that serves as the main food storage organ. On the other hand, a bulb is an underground stem that is modified for food storage and is typically round or oval in shape. The bulb has concentric layers of fleshy storage leaves, while corn does not have any fleshy layers. Additionally, corn does not have a flattened disc-shaped stem, no buds in the axils of the leaves, and no adventitious roots.