Home › Tamil Nadu SSLC (Class 10) › Biology › Plant and Animal Hormones › The internodal elongation seen in rice plants su…
The internodal elongation seen in rice plants suffering from Bakanae or foolish seedling disease is caused by a substance later identified as:
AAbscisic acid
BEthylene gas
CGibberellic acid
DIndole acetic acid
Answer & Solution
Correct answer: C. Gibberellic acid
1. Kurosawa observed Bakanae (foolish seedling) disease causing excess internodal elongation in rice.
2. The disease was caused by the fungus Gibberella fujikuroi.
3. The active substance from the fungus was identified as gibberellic acid.
4. Abscisic acid and ethylene are inhibitors, and auxin (IAA) is a different growth promoter, so they are ruled out.
_Source: Samacheer Kalvi (TN SCERT) Class 10 Science, Unit 16 Plant and Animal Hormones "Gibberellins", p.238_
Related questions
In the female, the luteinizing hormone (LH) from the anterior pituitary mainly brings abouThe hormone thymosin, which stimulates the production and differentiation of lymphocytes, The mineralocorticoid aldosterone, secreted by the zona glomerulosa of the adrenal cortex,Epinephrine and norepinephrine, released during stress and emotion, are called emergency hA diabetes mellitus patient shows hyperglycemia, glycosuria, polyuria, polydipsia and polyIn the islets of Langerhans, glucagon and insulin are secreted respectively by which cellsRemoval of the parathyroid glands during a thyroidectomy lowers parathormone and produces An enlargement of the thyroid gland appearing as a swelling in the neck due to inadequate