Question

Apical dominance is stimulated by auxin whereas it is inhibited by

• A. Cytokinin
• B. ABA
• C. Gibberellin
• D. Ethylene

Answer 1

The correct option is A Cytokinin

The phenomenon in which the apical bud suppresses the growth of lateral growth into branches is known as apical dominance.

Auxin promotes the phenomenon of apical dominance whereas cytokinin inhibits the phenomenon of apical dominance. These two hormones act antagonistically.

Cytokinins help overcome the apical dominance. They promote nutrient mobilization, which helps in the delay of leaf senescence. Presence of cytokinin in an area causes preferential movement of nutrients towards it. When applied to lateral buds, they help in their growth despite the presence of apical bud. They thus act antagonistically to auxin which promotes apical dominance. Therefore cytokinin can overcome apical dominance, caused by auxins.