Question
Explain the application of gibberellins.

Answer

  1. Gibberellins are growth promoting hormone and it is present in root tips, stem tips and seeds.
  2. Gibberellins break dormancy of bud, dormancy of seed.
  3. They promote seed germination in cereals by activating or synthesising enzyme amylase to produce sugar.
  4. Gibberellins induce elongation of the cells in stem hence increase in internode length is noticed.
  5. In rosette plants like cabbage it causes ‘bolting’ that is increase in internode length before flowering.
  6. Gibberellins are more effective in inducing parthenocarpy than auxins in plants like tomato, apple and pear.
  7. It is also used to increase fruit size and length of bunches in grapes.
  8. By its application genetically dwarf plants can be converted to phenotypically tall e.g. Maize.
  9. It overcomes requirement of vernalization, delays senescence and prevents abscission.
  10. Application of gibberellins causes production of male flowers on female plants.

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