NDA (II) 2024 General Ability Test · Question 55 of 141

Correct — A, Potato. A potato is an underground stem tuber whose surface carries small pits called 'eyes' — each eye is an axillary bud. When a piece of tuber bearing an eye is planted, the bud sprouts into a new plant, so the potato is the classic example of vegetative propagation through eye buds.

• (b)Ginger — Ginger is a rhizome (an underground stem) that propagates from buds on its nodes, but these are not called 'eyes' — the 'eye bud' term is specific to the potato, not ginger.
• (c)Onion — The onion is a bulb — a condensed stem with fleshy scale leaves — and it propagates via the bulb (and its daughter bulbs), not through eye buds.
• (d)Sugarcane — Sugarcane is propagated from stem cuttings called 'setts', each carrying nodal buds. The buds sprout, but sugarcane is described by 'setts/nodal buds', whereas 'eye buds' is the standard descriptor for the potato — so potato is the intended answer.

Vegetative (asexual) propagation grows a new plant from a vegetative part — root, stem or leaf — without seeds. The potato is a stem tuber: its 'eyes' are axillary buds sitting in shallow pits on the tuber surface, and each can grow into a full plant, making the tuber a natural propagation unit.

The phrase 'eye buds' is a strong pointer to the potato. Reason by the propagation part each crop uses: potato = eyes on a stem tuber; ginger = rhizome; onion = bulb; sugarcane = stem setts with nodal buds. Only the potato's buds are traditionally called 'eyes'.

• A potato is a stem tuber; its 'eyes' are axillary buds used for propagation.
• Ginger propagates by rhizome (an underground stem), onion by bulb.
• Sugarcane is propagated from stem cuttings ('setts') bearing nodal buds.
• Vegetative propagation produces genetically identical clones of the parent plant.

• Picking ginger or onion because they are also underground — their buds are not called 'eyes'.
• Confusing the potato (stem tuber) with sweet potato (a root).

Asked as 'which crop propagates by eyes / which is a modified stem' — link the plant part (tuber/rhizome/bulb/sett) to the crop.

• practice — not a real PYQ

  The 'eyes' of a potato that give rise to new plants are actually

  • (a)roots
  • (b)axillary buds
  • (c)seeds
  • (d)flowers

  Answer(b) axillary buds — each eye is a bud that can sprout into a new plant.

• practice — not a real PYQ

  Ginger is propagated vegetatively through its

  • (a)bulb
  • (b)rhizome
  • (c)eye buds
  • (d)leaf

  Answer(b) rhizome — ginger is an underground stem (rhizome).