Diffusion pressure deficit is the amount by which two solutions differ in their

Options

A. T.P.
B. O.P
C. D.P.
D. W.P.

Answer

To solve the question regarding Diffusion Pressure Deficit (DPD) and its relation to different pressures, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Diffusion Pressure Deficit (DPD)**:
- DPD is defined as the difference in diffusion pressure between two solutions. It indicates how much lower the diffusion pressure of a solution is compared to pure water.

2. **Identifying the Components**:
- In the context of plant physiology, we have several pressures to consider:
- **Osmotic Pressure (BOP)**: The pressure required to prevent the flow of water into a solution via osmosis.
- **Turgor Pressure (TP)**: The pressure exerted by the fluid inside the cell against the cell wall.
- **Wall Pressure (WP)**: The pressure exerted by the cell wall against the turgor pressure.
- **Diffusion Pressure (DP)**: The potential of water to diffuse, which is influenced by the concentration of solutes.

3. **Formulating the DPD Equation**:
- The formula for calculating DPD can be expressed as:
\[ DPD = DP_{pure\ water} - DP_{solution} \]
- Since pure water has the highest diffusion pressure, DPD effectively measures how much lower the diffusion pressure of a solution is compared to pure water.

4. **Conclusion**:
- The question asks what DPD measures the difference in. The correct answer is that DPD measures the difference in diffusion pressure (DP) between two solutions.

5. **Final Answer**:
- Therefore, the answer to the question is **C. Diffusion Pressure (DP)**.