A man made allopolyploid cereal crop is

Options

A. Hordeum vulgare
B. Triticale
C. Raphanobrassica
D. Zea mays

Answer

### Step-by-Step Solution:

1. **Understanding Allopolyploidy**:
- Allopolyploidy refers to a type of polyploidy where the chromosomes are derived from different species. It is a significant mechanism in plant evolution, leading to the creation of new species.

2. **Identifying Man-Made Allopolyploid Cereal Crops**:
- The question specifically asks for a man-made allopolyploid cereal crop. This means we need to look for a cereal crop that has been artificially created through hybridization of two different species.

3. **Analyzing the Given Options**:
- The options provided are:
- a) Hortium vulgaris
- b) Strytegill
- c) Rhaenobrassica
- d) Triticale (Gea maize)
- We need to determine which of these is a man-made allopolyploid cereal crop.

4. **Identifying Triticale**:
- Triticale is a hybrid created from the crossing of two species: Triticum (wheat) and Secale (rye). It is specifically developed as a cereal crop and is recognized as a man-made allopolyploid.

5. **Conclusion**:
- Based on the analysis, the correct answer to the question is **Triticale** (option d).

### Final Answer:
The man-made allopolyploid cereal crop is **Triticale**.

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