Wide hybridisation has been used for producing

Options

A. Haploids
B. Dihaploids from tetraploids
C. Trihaploids from hexaploids
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Wide Hybridization**: Wide hybridization refers to the process of crossing organisms that are genetically distant, often from different genera or even families. This is unlike traditional hybridization, which typically occurs between closely related species.

2. **Types of Hybridization**: In wide hybridization, the hybridization can occur between:
- Closely related species (intra-specific or inter-specific)
- Distantly related species (inter-generic or inter-familial)

3. **Outcomes of Wide Hybridization**: The process can lead to the creation of various types of hybrids, including:
- Haploids (1n)
- Diploids (2n)
- Triploids (3n)
- Tetraploids (4n)
- Pentaploids (5n)
- Hexaploids (6n)

4. **Applications of Wide Hybridization**: This technique is commonly used in plant breeding and genetic research to introduce new traits, improve disease resistance, or enhance yield. It allows for a broader genetic base, which can be beneficial for the adaptability and resilience of the offspring.

5. **Conclusion**: Therefore, wide hybridization has been used for producing a variety of hybrids, including those with different ploidy levels. The correct answer to the question is that wide hybridization can produce all of these types of hybrids.

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