Norin gene' of dwarfness in wheat originated through spontaneous mutation in

Options

A. India
B. Japan
C. Mexico
D. U.S.S.R.

Answer

To answer the question regarding the origin of the 'Norin gene' of dwarfness in wheat, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Norin Gene**: The Norin gene is associated with dwarfness in wheat, which is an important trait for improving crop yield and resistance to lodging.

2. **Identifying the Origin**: The question asks about the origin of this gene through spontaneous mutation.

3. **Analyzing the Options**: The options provided are:
- A) India
- B) Japan
- C) Mexico
- D) USSR

4. **Researching the Background**: The Norin gene was discovered in Japan in the 1930s. Specifically, it was identified in the variety of wheat known as 'Norin 10'.

5. **Confirming the Correct Answer**: Since the Norin gene originated in Japan, the correct answer is option B) Japan.

### Final Answer:
The 'Norin gene' of dwarfness in wheat originated through spontaneous mutation in **Japan**.

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