Plant Growth and Development Question 14
14. Removal of shoot tips is a very useful technique to boost the production of tealeaves. This is because :
[2019]
(a) Gibberellins delay senescence of leaves.
(b) Gibberellins prevent bolting and are inactivated.
(c) Auxins prevent leaf drop at early stages.
(d) Effect of auxins is removed and growth of lateral buds is enhanced.
Show Answer
Answer : d
Hints & Solutions
(d) Auxin shows apical dominance. Removal of auxin by removal of shoot tips prevents the apical dominance and promotes the growth of lateral buds which is a very useful in tea leaves production. The plant invests its energy into growing taller in order to maximize the plant’s exposure to light. Removing the shoot tip (“cutting back”) will remove the source of auxin and will stimulate the growth of axillary buds, and make the plant thicker and bushier. 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.
