Xenia effect was first observed in

Options

A. Wheat
B. Groundnut
C. Pea
D. Maize

Answer

### Step-by-Step Solution:

1. **Understanding the Xenia Effect**:
- The Xenia effect refers to the influence of pollen on the characteristics of seeds and fruits of a fertilized plant. It is distinct from the genetic contribution of the pollen to the next generation.

2. **Identifying the Plant**:
- The Xenia effect is particularly noted in plants, and it has been most profoundly observed in maize (corn).

3. **Characteristics of Maize**:
- Maize is a monoecious plant, meaning it has both male and female flowers on the same plant, which facilitates cross-pollination.

4. **Historical Context**:
- The term "Xenia" was coined in 1881 by the botanist Wilhelm Albers Focke, who studied the effects of pollen on maternal tissues, including the seed coat and pericarp.

5. **Conclusion**:
- Based on the information, the Xenia effect was first observed in maize. Therefore, the correct answer to the question is maize.

### Final Answer:
The Xenia effect was first observed in maize.

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