Biology · Plant Growth and Development · NEET
It inhibits them. This is the exact NCERT wording that NEET tests: the growing apical bud inhibits the growth of the lateral (axillary) buds. Many students wrongly read the word 'dominance' as 'helps'. Dominance here means the tip dominates and holds back the side buds. In NEET 2025 the statement 'Apical dominance promotes the growth of lateral buds' was marked WRONG for this reason.
Auxin (IAA). The apical bud (shoot tip) is a growing apex, and auxin is made in the growing apices of stems. This auxin moves downward and suppresses the lateral buds. So apical dominance is an auxin effect. Remember auxin's other jobs too: rooting in cuttings, parthenocarpy, xylem differentiation, and 2,4-D as a weed killer.
The shoot tip is the auxin factory. When you cut it off (decapitation), no more auxin travels down to hold back the axillary buds. Free from auxin control, the lateral buds now grow into branches. NCERT: 'Removal of shoot tips (decapitation) usually results in the growth of lateral buds.' This is why hedges, tea, and many crops are pruned to get a bushy, spread-out plant.
Cytokinins. NCERT clearly states 'Cytokinins help overcome the apical dominance.' So there are two ways to release the side buds: physically remove the tip (decapitation), or apply cytokinin. This appears in NEET matching questions, for example Cytokinin matched with 'overcoming apical dominance'.
To get more leaves for harvest. Removing the shoot tips takes away the auxin, so the lateral buds grow and the tea bush becomes fuller with many new shoots and leaves. NEET 2023 asked exactly this: the correct reason is that the effect of auxins is removed and growth of lateral buds is enhanced.
Removal of shoot tips is a very useful technique to boost the production of tea-leaves. This is because
Read the following statements on plant growth and development. A. Parthenocarpy can be induced by auxins. B. Plant growth regulators can be involved in promotion as well as inhibition of growth. C. Dedifferentiation is a pre-requisite for re-differentiation. D. Abscisic acid is a plant growth promoter. E. Apical dominance promotes the growth of lateral buds. Choose the option with all correct statements.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
The growing apical bud makes auxin that stops the lateral (axillary) buds below it from growing.
Decapitation is the removal of the shoot tip (apical bud). It removes the auxin source, so lateral buds grow and the plant becomes bushy.
Auxin maintains apical dominance (it suppresses side buds). Cytokinin helps overcome apical dominance, and physically removing the tip also releases the side buds.
Pruning tea plants and hedges: removing shoot tips lets lateral buds grow, giving more leaves and a fuller, bushy plant.
