What is the source of auxin?

What is the source of auxin?
  1. tips of coleoptiles of oat seedlings
  2. sterile filtrates of the fungus Gibberella fujikuroi
  3. tips of coleoptiles of rice seedlings
  4. tips of coleoptiles of canary grass

Solution

Auxin was isolated by F.W. Went from tips of coleoptiles of oat seedlings.

Asked in: NCERT

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