Orthodox seeds can be preserved for long periods at a temperature of

Options

A. `-196^@C`
B. `-10^@ " to " -20^@C`
C. `0^@ - 4^@C`
D. `10^@ " to " 15^@C`

Answer

To solve the question regarding the preservation temperature of orthodox seeds, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Orthodox Seeds**:
- Orthodox seeds are seeds that can be stored for long periods due to their desiccation tolerance. This means they can survive in low moisture conditions (around 5-6% moisture).

2. **Identify the Types of Seeds**:
- There are three categories of seed physiological behavior during storage:
- Orthodox seeds (long-lived and desiccation tolerant)
- Recalcitrant seeds (cannot be stored for long periods and sensitive to moisture)
- Intermediate seeds (show characteristics of both orthodox and recalcitrant seeds).

3. **Determine the Storage Conditions for Orthodox Seeds**:
- Orthodox seeds can be preserved for extended periods, typically requiring specific temperature conditions for optimal storage.

4. **Analyze the Given Temperature Options**:
- The options provided are:
- A) -196°C
- B) -10 to -20°C
- C) 0°C to 4°C
- D) 10°C to 15°C

5. **Select the Correct Temperature Range**:
- Based on the information about orthodox seeds, the most common temperature range for their preservation is between -10°C to -20°C. This range allows for long-term storage while maintaining the viability of the seeds.

6. **Final Answer**:
- Therefore, the correct answer is **B) -10 to -20°C**.