Most efficient and ultimate method of crop improvement that creates greatest genetic variability is

Options

A. Mass selection
B. Intergeneric hybridization
C. Mutation breeding
D. Polyploidy breeding

Answer

**Step-by-Step Solution:**

1. **Understanding Crop Improvement Methods**: There are various methods for crop improvement, each with its own mechanism and effectiveness in creating genetic variability.

2. **Identifying the Options**: The options provided are:
- Mass selection
- Intergeneric hybridization
- Mutation breeding
- Polyploidy breeding

3. **Analyzing Each Option**:
- **Mass Selection**: This method involves selecting individuals from a population based on desirable traits. While it can improve certain characteristics, it does not create significant genetic variability.
- **Intergeneric Hybridization**: This involves crossing plants from different genera within the same family. It can introduce new traits but is limited in creating genetic variability compared to other methods.
- **Mutation Breeding**: This method involves exposing seeds to chemicals or radiation to induce mutations. It is known for generating a wide range of genetic variability and is often referred to as variation breeding.
- **Polyploidy Breeding**: This method involves manipulating the number of chromosome sets in plants. While it can lead to certain advantages, it is not primarily focused on creating genetic variability.

4. **Conclusion**: After analyzing all the options, mutation breeding stands out as the most efficient and ultimate method of crop improvement that creates the greatest genetic variability.

5. **Final Answer**: The most efficient and ultimate method of crop improvement that creates the greatest genetic variability is **mutation breeding**.

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