Plant Growth and Development Question 15
15. In order to increase the yield of sugarcane crop, which of the following plant growth regulators should be sprayed?
[2019]
(a) Cytokinins
(b) Ethylene
(c) Auxins
(d) Gibberellins
Show Answer
Answer : d
Hints & Solutions
(d) Gibberellins (GAs) regulate various developmental processes, including stem elongation, germination, dormancy, flowering, flower development and leaf and fruit senescence. When gibberellin is sprayed on sugarcane crop, the length of the stem increases. Kurosawa, a Japanese botanist, discovered gibberellin while investigating the rice foolish seedling disease in which spindly seedlings are formed due to GA like compounds produced by the fungus (Gibberella fujikuroi) infecting the plant. They are produced in the plant cell’s plastids, and are eventually transferred to the endoplasmic reticulum of the cell, where they are modified and prepared for use. There are more than 70 gibberellins isolated. They are GA1, GA2, GA3 and so on. GA3 Gibberellic acid is the most widely studied plant growth regulators.
