The axillary bud (or lateral bud) is an embryonic shoot located in the axil of a leaf. Each bud has the potential to form shoots, and may be specialized in producing either vegetative shoots (stems and branches) or reproductive shoots (flowers). Once formed, a bud may remain dormant for some time, or it may form a shoot immediately.
Axillary bud do not become actively growing shoots on plants with strong apical dominance (the tendency to grow just the terminal bud on the main stem). Apical dominance occurs because the shoot apical meristem produces auxin which prevents axillary buds from growing. The axillary buds begin developing when they are exposed to less auxin, for example if the plant naturally has weak apical dominance, if apical dominance is broken by removing the terminal bud, or if the terminal bud has grown far enough away for the auxin to have less of an effect.
Axillary buds can be used to differentiate if the plant is single-leafed or multi-leafed. Simply count the number of leaves after an axillary bud. If there is only one leaf, then the plant is considered single-leafed, if not is is considered multi-leafed.
An example of axillary buds are the eyes of the potato.
Effects of Auxin
As the apical meristem grows and forms leaves, it leaves behind a region of meristematic cells at the node between the stem and the leaf. These axillary buds are usually dormant, inhibited by auxin produced by the apical meristem, which is known as apical dominance.
If the apical meristem is removed, or has grown a sufficient distance away from an axillary bud, the axillary bud may become activated (or more appropriately freed from hormone inhibition). Like the apical meristem, axillary buds can develop into a stem or flower.
Plant Diseases That Affect Axillary Buds
- Adrian D. Bell; Alan Bryan (2008). Plant Form: An Illustrated Guide to Flowering Plant Morphology. Timber Press. p. 306. ISBN 978-0-88192-850-1.
- Adrian D. Bell; Alan Bryan (2008). Plant Form: An Illustrated Guide to Flowering Plant Morphology. Timber Press. p. 18. ISBN 978-0-88192-850-1.
- Linda Berg (23 March 2007). Introductory Botany: Plants, People, and the Environment, Media Edition. Cengage Learning. p. 238. ISBN 0-534-46669-9.
|This botany article is a stub. You can help Wikipedia by expanding it.|