All are correct except -

Options

A. Mycorrhizal fungi form a network around the young root and they penetrate the root cells
B. Mycorrhizae helps the plant to absorb water and minerals
C. Root provides sugar and nitrogenous organic compounds to the mycorrhizae
D. Pinus seed can germinate and establish without mycorrhizae

Answer

**Step-by-Step Solution:**

1. **Understanding Mycorrhiza**: Mycorrhiza is a symbiotic association between fungi and higher plants, primarily gymnosperms. This relationship is beneficial for both organisms.

2. **Evaluating the Options**:
- **Option 1**: Mycorrhizal fungi form a network around the young root and penetrate the root cells.
- This statement is correct as mycorrhizal fungi do indeed surround and penetrate the root cells to facilitate nutrient exchange.

- **Option 2**: Mycorrhiza helps the plant to absorb water and minerals.
- This statement is also correct. Mycorrhiza enhances the plant's ability to absorb water and essential minerals from the soil.

- **Option 3**: Root provides sugar, nitrogenous, or organic compounds to the mycorrhiza.
- This statement is correct as well. The roots of the plant supply sugars and nitrogenous compounds to the mycorrhizal fungi, which they need for growth.

- **Option 4**: Mycorrhiza can germinate and establish without mycorrhiza.
- This statement is incorrect. Plants that form mycorrhizae typically lack root hairs and caps, making them dependent on the fungi for survival. Therefore, they cannot germinate and establish without mycorrhiza.

3. **Conclusion**: Since option 4 is the only incorrect statement, it is the answer to the question.

**Final Answer**: The incorrect statement is option 4: "Mycorrhiza can germinate and establish without mycorrhiza."

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