Question

How much sucrose is generally required for the initiation of androgenesis in plants?

• A. Up to 1.5%
• B. Up to 2.5%
• C. Up to 3.5%
• D. More than 5.0%

Hint:

Anther Culture needs High Sugar. The high osmotic pressure "shocks" the pollen into becoming an embryo instead of a sperm cell.

Answer 1

The Correct Option is D

Concept: Sucrose in tissue culture media serves two roles: a carbon/energy source and an osmotic stabilizer. Different developmental pathways require different osmotic pressures.

Step 1: The High Sucrose Requirement for Pollen.
Standard plant media (like MS) usually contain 2% to 3% sucrose. However, androgenesis (especially anther culture) often requires a significantly higher concentration of sucrose—typically ranging from 6% to 12%.

Step 2: Why High Sucrose?
The high sucrose concentration (more than 5.0%) acts as an osmotic stressor. This stress is critical for "reprogramming" the pollen grain. It triggers the cell to switch from its normal gametophytic pathway (pollen tube growth) to a sporophytic pathway (forming an embryo).

Step 3: Conclusion.
Among the given options, androgenesis is characterized by these higher-than-average sucrose requirements, making option (4) the correct choice.