Pure line selection is used in __________________

Answer

**Step-by-Step Solution:**

1. **Understanding Pure Line Selection**:
Pure line selection is a breeding method used to enhance desirable traits in plants. It involves selecting individuals from a genetically uniform population (pure lines) that exhibit specific traits.

2. **Application of Pure Line Selection**:
The primary application of pure line selection is in self-pollinating crops. This means that the plants can fertilize themselves, leading to offspring that are genetically similar to the parent plant.

3. **Historical Example**:
A significant historical example of pure line selection is the work of Gregor Mendel. He conducted experiments with pea plants, where he selected pure lines of tall plants and crossed them with pure lines of dwarf plants.

4. **Genetic Uniformity**:
In pure line selection, both parent plants are homozygous, meaning they have identical alleles for the traits being studied. This ensures that the offspring will consistently express the desired traits.

5. **Benefits of Pure Line Selection**:
The benefits of this method include the ability to maintain desirable traits without the introduction of unwanted genetic variations, such as diseases or mutations. This leads to a stable and predictable outcome in the offspring.

6. **Conclusion**:
Therefore, pure line selection is primarily used in self-pollinating crops to ensure the propagation of desirable traits while minimizing genetic variation.

**Final Answer**: Pure line selection is used in self-pollinating crops.

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