Which of the following is used to determine the rate of transpiration in plants

Options

A. Porometer
B. Potometer
C. Auxanometer
D. Tensiometer

Explanation

To determine the rate of transpiration in plants, we need to analyze the given options one by one. Here’s a step-by-step solution:

### Step 1: Understand Transpiration
Transpiration is the process by which water vapor is lost from the aerial parts of plants, primarily through small openings called stomata. Measuring the rate of transpiration helps us understand water loss and plant health.

### Step 2: Evaluate the Options
We have four options to consider for measuring the rate of transpiration:

1. **Porometer**:
- A porometer is used to measure the size of stomata, not the rate of transpiration. Therefore, this option is incorrect.

2. **Potometer**:
- A potometer is specifically designed to measure the rate of water uptake in plants, which is directly related to the rate of transpiration. This option is correct.

3. **Oxanometer**:
- An oxanometer measures the growth of plants, particularly vertical growth, and is not related to transpiration. Thus, this option is incorrect.

4. **Tensiometer**:
- A tensiometer measures soil moisture content, which indirectly relates to plant water uptake but does not measure transpiration directly. Hence, this option is also incorrect.

### Step 3: Conclusion
After evaluating all the options, we conclude that the correct instrument used to determine the rate of transpiration in plants is the **Potometer**.

### Final Answer
The correct answer is **Potometer**.

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