which of the following statement is incorrect w.r.t. Azolla? (a) it is an aquatic water fern (b) it is used as biofertilizer (c) it is homosporous vascular cryptogam (d) it shows symbiotic association with alga Anabaena which fixes atmospheric nitrogen

Options

A. all except (c)
B. (a) & (b)
C. (c) only
D. (d) only

Answer

To determine which statement about Azolla is incorrect, let's analyze each option step by step.

1. **Statement (a): "It is an aquatic water fern."**
- Azolla is indeed an aquatic fern that grows in water bodies. It floats on the surface of water and is commonly found in ponds and rice fields.
- **Conclusion:** This statement is correct.

2. **Statement (b): "It is used as biofertilizer."**
- Azolla is widely recognized for its use as a biofertilizer, particularly in rice cultivation. It enhances soil fertility by fixing atmospheric nitrogen through its symbiotic relationship with the cyanobacterium Anabaena.
- **Conclusion:** This statement is correct.

3. **Statement (c): "It is homosporous vascular cryptogam."**
- Azolla is actually heterosporous, meaning it produces two types of spores: microspores and megaspores. Homosporous plants produce only one type of spore. Therefore, this statement is incorrect.
- **Conclusion:** This statement is incorrect.

4. **Statement (d): "It shows symbiotic association with alga Anabaena which fixes atmospheric nitrogen."**
- Azolla does have a symbiotic relationship with the cyanobacterium Anabaena, which is known for its ability to fix atmospheric nitrogen. This relationship is beneficial for both organisms and contributes to soil fertility.
- **Conclusion:** This statement is correct.

Based on the analysis, the incorrect statement regarding Azolla is:

**Final Answer:** (c) it is homosporous vascular cryptogam.

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