Vicia faba and pisum sativum are recommended for rotaion of crops because they

Options

A. require small amount of water
B. are cash crops
C. help in nitrogen fixation of soil
D. kill all the harmful insects.

Answer

**Step-by-Step Solution:**

1. **Understanding Crop Rotation:**
- Crop rotation is the practice of growing different types of crops in the same area in sequential seasons. This method helps in maintaining soil fertility and reducing soil erosion.

2. **Identifying the Plants:**
- The two plants mentioned in the question are Vicia faba (broad bean) and Pisum sativum (pea). Both of these plants belong to the legume family.

3. **Importance of Legumes:**
- Leguminous plants have a unique ability to fix atmospheric nitrogen through a symbiotic relationship with nitrogen-fixing bacteria (like Rhizobium) present in their root nodules.

4. **Nitrogen Fixation:**
- These bacteria convert atmospheric nitrogen (N2) into ammonia (NH3), which can then be transformed into nitrates (NO3-) and nitrites (NO2-) that plants can absorb and utilize for growth.

5. **Benefits of Using Vicia faba and Pisum sativum in Crop Rotation:**
- By incorporating these legumes into crop rotation, the nitrogen content of the soil is replenished, enhancing soil fertility. This reduces the need for synthetic fertilizers and promotes sustainable agricultural practices.

6. **Conclusion:**
- Therefore, Vicia faba and Pisum sativum are recommended for crop rotation because they help in nitrogen fixation, improving soil fertility for subsequent crops.

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