Stem tubers are the swollen end of the special underground stem. It is arising from the axil of the lower leaf. Adventitious roots are absent and possess slender internodes. The buds develop from the tubers when it is planted in the soil giving rise to branches. These branches develop to aerial shoot system and underground root system which have swollen tip with food materials. Example: Potato In Potato the small depressions present on the tubers are called as the eye of the potato. The bud is a means of vegetative propagations in Potato.