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Question: Answered & Verified by Expert
The pineapple which under natural condition is difficult to blossom has been made to produce fruits throughout the year by application of:
BiologyPlant - Growth and DevelopmentNEETNEET 2013 (Karnataka)
Options:
  • A NAA, 2, 4-D
  • B Phenyl acetic acid
  • C Cytokinin
  • D IAA, IBA
Solution:
2318 Upvotes Verified Answer
The correct answer is: NAA, 2, 4-D
NAA (alpha Naphthalene acetic acid) and 2,4 Dichlorophenoxy acetic acid are synthetic auxins. Normally, auxins inhibit flowering. In litchi and pineapple, it promotes flowering.
Related Theory
Antiauxins are a group of chemicals that can prevent auxin-action in plants. Transcinnamic acid, ascorbic acid, 7-phenyl butyric acid are some of these antiauxins. Probably, an antiauxin competes with an auxin for the same site of reaction and thus inhibits auxin-action.

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