Question

Optimum soil temperature for potato crop in tropics is

• A. \(17 ^\circ\text{C}\)
• B. \(20 ^\circ\text{C}\)
• C. \(25 ^\circ\text{C}\)
• D. \(28 ^\circ\text{C}\)

Hint:

Remember that potato is a cool-season crop. Tuberization requires cooler conditions than foliage growth; thus, the lower value in the \(17\text{--}20 ^\circ\text{C}\) range (\(17 ^\circ\text{C}\)) is the critical optimum.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Potato (Solanum tuberosum) is a cool-season crop.
Its underground tuberization phase (initiation and growth of tubers) is highly sensitive to the surrounding soil temperature.

Step 3: Detailed Explanation:
1. The physiological process of tuberization is heavily suppressed by warm temperatures.
2. Standard agronomic studies show that the optimum soil temperature for potato tuber initiation and development is \(17 ^\circ\text{C}\) to \(20 ^\circ\text{C}\).
3. While vegetative foliar growth is supported at slightly warmer temperatures (\(20 ^\circ\text{C}\) to \(24 ^\circ\text{C}\)), the ideal target for securing maximum tuber development (especially in the warm tropical regions) is maintaining a cool soil zone near \(17 ^\circ\text{C}\).
At temperatures exceeding \(26 ^\circ\text{C}\), tuberization is severely restricted, and it completely ceases above \(30 ^\circ\text{C}\).

Step 4: Final Answer:
The correct option is 1, which corresponds to \(17 ^\circ\text{C}\).