Question

Which one of the following acts as a Carbon source in plant tissue culture?

• A. \( \text{Sucrose} \)
• B. \( \text{Auxin} \)
• C. \( \text{Cytokinins} \)
• D. \( \text{Charcoal} \)

Hint:

Most media formulations, such as Murashige and Skoog (MS) media, typically use sucrose at a concentration of 2% to 3%.

Answer 1

The Correct Option is A

Concept: Plant tissue culture involves growing plant cells or organs in a sterile, nutrient-rich environment.
• While whole plants are autotrophic (make their own food), cultured tissues often lack sufficient photosynthetic capacity.
• Therefore, an external source of energy and carbon must be provided in the media.

Step 1: Identifying Media Components.
Auxins and Cytokinins are plant hormones (growth regulators) used to control root and shoot development. Activated charcoal is sometimes added to absorb toxic metabolites or provide dark conditions.

Step 2: The Primary Carbon Source.
Carbohydrates serve as the carbon and energy source for the cells. Sucrose is the most commonly used carbon source because it is cheap, highly soluble, and easily utilized by plant cells. During autoclaving and culture, it breaks down into glucose and fructose, which are then absorbed by the tissues. Final Answer: Sucrose is the standard carbon source used in plant tissue culture media.