The embryonic shoot which lies at the intersection of the petiole and stem of a plant is known as the axillary bud.
Certain regions of the meristematic cells are left behind the node located in the middle of the leaf and stem as the apical meristem grows and forms leaves. The term “apical dominance” refers to the process wherein the axillary buds remain dormant and is reserved by the auxin that was produced by the apical meristem. Once the apical meristem was removed or when it has developed an adequate distance from the axillary bud, the latter can be freed from inhibition of hormone or normally termed as becoming activated. Axillary buds can soon develop into a flower or stem, like the apical meristem.
The axillary bud is a specialized part of the plant that is used in differentiating as to whether the plant is single-leafed or multi-leafed. A single leaf after the axillary bud means that the plant is single-leafed and this goes the same with multi-leafed plants.
Phytoplasmas, a certain plant disease, can give rise to the proliferation of axillary buds thus, causing plants to develop a bushy-like appearance. Topophysis can also affect the growth as well as the differentiation of position of the axillary buds found along the shoot.