For phycomycetes class of fungus, incorrect statement is

Options

A. their mycelium is aseptate and coenocytic
B. the fusion of gametes results in the formation of zygospore.
C. modes of asexual reproduction are motile aplanospores and non-motile zoospores
D. Parasitic fungus Albugo produces white sports on mustard leaves.

Answer

To determine the incorrect statement regarding the phycomycetes class of fungi, we can analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Phycomycetes**:
- Phycomycetes, also known as lower fungi, are primarily found in aquatic habitats and decaying organic matter. They thrive in moist and damp environments.

2. **Evaluating the First Statement**:
- "Their mycelium is septate and coenocytic."
- This statement is **correct**. In phycomycetes, the mycelium can be coenocytic (aseptate) or septate, but they typically exhibit coenocytic characteristics.

3. **Evaluating the Second Statement**:
- "The fusion of gametes results in the formation of zygospore."
- This statement is **correct**. In phycomycetes, the fusion of gametes leads to the formation of a zygospore.

4. **Evaluating the Third Statement**:
- "Modes of asexual reproduction are motile aplanospores and non-motile zoospores."
- This statement is **incorrect**. The correct information is that phycomycetes reproduce asexually through motile zoospores and non-motile aplanospores. The terms are reversed in this statement.

5. **Evaluating the Fourth Statement**:
- "Parasitic fungus Albugo produces white spots in mustard leaves."
- This statement is **correct**. Albugo is known to cause white rust disease in mustard plants, leading to the appearance of white spots.

6. **Conclusion**:
- After evaluating all statements, the incorrect statement is the third one regarding the modes of asexual reproduction.

### Final Answer:
The incorrect statement is: "Modes of asexual reproduction are motile aplanospores and non-motile zoospores."

---