In maize, hybrid vigour is exploited by

Options

A. crossing of two inbred parental lines
B. harvesting seeds from the most productive plants
C. inducing mutation
D. bombarding the seeds with DNA

Answer

**Step-by-Step Solution:**

1. **Understanding Hybrid Vigour**: Hybrid vigour, also known as heterosis, refers to the phenomenon where the offspring (hybrids) exhibit superior qualities compared to their parents. This can include increased growth rate, fertility, and overall yield.

2. **Identifying the Context**: In maize (Zea mays), hybrid vigour is particularly important for improving crop production. Maize is a cereal grain and is known for its ability to produce high yields when hybrid varieties are used.

3. **Exploring the Options**: The question provides several options regarding how hybrid vigour is exploited in maize:
- A) Crossing of two inbred parental lines
- B) Harvesting seeds from the most productive plants
- C) Inducing mutation
- D) Bombarding the seeds with DNA

4. **Analyzing the Correct Option**: The most effective method for exploiting hybrid vigour in maize is through the **crossing of two inbred parental lines**. This method takes advantage of the genetic diversity between the inbred lines to produce hybrids that outperform their parents.

5. **Conclusion**: Therefore, the correct answer to the question is **A) crossing of two inbred parental lines**.

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