Which is incorrect about phycomycetes ?

Options

A. (a) Mycelium is aseptate and coenocytic
B. (b) A zygospore is formed by fusion of gametes
C. (c) Asexual reproduction takes place by motile aplanospores and non-motile zoospores
D. (d) White spots seen on mustard leaves are due to parasitic fungus Albugo

Answer

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

### Step 1: Analyze Option A
**Statement:** Mycelium is aseptic and sinusitic.
**Explanation:** Phycomycetes, also known as lower fungi, have mycelium that is indeed aseptic (meaning it lacks septa) and sinusitic (meaning it contains multiple nuclei). This statement is correct.

### Step 2: Analyze Option B
**Statement:** A zygospore is formed by the fusion of gametes.
**Explanation:** A zygospore is a type of sexual reproductive structure that forms when gametes fuse. This statement is also correct.

### Step 3: Analyze Option C
**Statement:** Asexual reproduction takes place by motile aplanospores and non-motile zoospores.
**Explanation:** This statement is incorrect. In phycomycetes, aplanospores are non-motile, while zoospores are motile. Therefore, the statement incorrectly describes the types of spores.

### Step 4: Analyze Option D
**Statement:** White spots seen on mustard leaves are due to the parasitic fungus Albugo.
**Explanation:** Albugo is indeed a parasitic fungus that causes white spots on mustard leaves. This statement is correct.

### Conclusion
The incorrect statement about phycomycetes is **Option C**: "Asexual reproduction takes place by motile aplanospores and non-motile zoospores."

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