Question

A natural growth regulator is

• A. Ethylene
• B. NAA
• C. 2, 4-D
• D. Benzyladenine

Answer 1

The correct option is A Ethylene

Ethylene is a simple gaseous plant growth regulator. It is synthesised in large amounts by tissues undergoing senescence and ripening fruits. Influences of ethylene on plants include horizontal growth of seedlings, swelling of the axis and apical hook formation in dicot seedlings. Ethylene promotes senescence and abscission of plant organs especially of leaves and flowers. Ethylene is highly effective in fruit ripening. It enhances the respiration rate during ripening of the fruits. This rise in rate of respiration is called as respiratory climactic.

Thus, the correct answer is option A.