There are several factors that contribute to apical dominance:
* Auxin: Auxin is a plant hormone that is produced in the apical meristem and transported downwards through the stem. Auxin inhibits the growth of lateral buds by preventing the cells in the lateral buds from dividing.
* Cytokinin: Cytokinin is another plant hormone that is produced in the roots and transported upwards through the stem. Cytokinin promotes the growth of lateral buds by stimulating the cells in the lateral buds to divide.
* Gibberellin: Gibberellin is a plant hormone that is produced in the leaves and transported downwards through the stem. Gibberellin also promotes the growth of lateral buds by stimulating the cells in the lateral buds to divide.
* Abscisic acid: Abscisic acid is a plant hormone that is produced in response to stress conditions, such as drought or high temperatures. Abscisic acid inhibits the growth of lateral buds by preventing the cells in the lateral buds from dividing.
The balance between these four hormones determines whether apical dominance occurs or not. In most plants, the levels of auxin and abscisic acid are higher than the levels of cytokinin and gibberellin, which results in apical dominance. However, in some plants, the levels of cytokinin and gibberellin are higher than the levels of auxin and abscisic acid, which results in the growth of lateral buds and a more bushy plant.
