1
The pineapple which under natural condition is difficult to blossom has been made to produce fruits throughout the year by application of
- NAA, 2,4-D
- Phenyl acetic acid
- Cytokinin
- IAA, IBA.
Answer
(1) NAA, 2,4-D
Solution
As per NCERT, auxins promote flowering, e.g. in pineapples.
⇒ In practice, synthetic auxins such as NAA (naphthalene acetic acid) and 2,4-D (2,4-dichlorophenoxyacetic acid) are sprayed on pineapple plants to induce uniform flowering and fruiting throughout the year.
∵ Synthetic auxins are cheaper and more stable than natural auxins (IAA, IBA), they are the ones used commercially.
∴ Pineapple is made to flower by the application of NAA and 2,4-D.
Answer: (1)
NEET 2013 (Karnataka)