Which of the following plants are used as green manure in crop fields and in sandy soils?

Options

A. Crotalaria juncea and Alhagi camelorum
B. Calotropis procera and phyllanthus niruri
C. Saccharum munja and Lantana camara
D. Dichanthium annulatum and Acacia nilotica

Answer

To answer the question regarding which plants are used as green manure in crop fields and sandy soils, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Green Manure**:
- Green manure refers to the practice of growing certain plants and then incorporating them back into the soil to improve its fertility and structure. This is often done by leaving uprooted or mowed parts of the plants in the field.

2. **Identifying Suitable Plants**:
- We need to identify which of the given options are known to be used as green manure specifically in sandy soils.

3. **Evaluating the Options**:
- The options provided include various plants. We need to check which of these are recognized for their use as green manure.
- The transcript mentions two specific plants: **Crotalaria juncea** (commonly known as sun hemp) and **Alhagi camelorum**.

4. **Confirming Their Use**:
- Both **Crotalaria juncea** and **Alhagi camelorum** belong to the family Fabaceae (legumes) and are known for their ability to improve soil fertility, especially in sandy soils.
- Crotalaria juncea is also noted for its potential as a source of fiber and biofuel.

5. **Conclusion**:
- Based on the information, the correct answer to the question is **Crotalaria juncea** and **Alhagi camelorum** as they are used as green manure in crop fields and sandy soils.

### Final Answer:
The plants used as green manure in crop fields and sandy soils are **Crotalaria juncea** and **Alhagi camelorum**.

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