If wheat field is inoculated with Rhizobium :-

Options

A. Soil will become nitrogen rich
B. No effect on soil nitrogen
C. Soil will be depleted of nitrogen
D. Soil will become rich in calcium

Answer

**Step-by-Step Solution:**

1. **Understanding Rhizobium**: Rhizobium is a type of bacteria that forms a symbiotic relationship with leguminous plants (family Leguminaceae). It is known for its ability to fix atmospheric nitrogen into a form that plants can use.

2. **Role of Rhizobium**: In leguminous plants, Rhizobium bacteria live in root nodules and convert nitrogen gas from the atmosphere into ammonia, which is then used by the plant for growth. In return, the plant provides carbohydrates to the bacteria.

3. **Identifying the Plant Family**: Wheat (Triticum spp.) belongs to the family Poaceae (grasses), not Leguminaceae. This distinction is crucial because Rhizobium is effective only with legumes.

4. **Effect of Inoculation on Wheat**: Since wheat does not form a symbiotic relationship with Rhizobium, inoculating a wheat field with this bacteria does not enhance nitrogen fixation or significantly affect the nitrogen content in the soil.

5. **Conclusion**: Therefore, if a wheat field is inoculated with Rhizobium, there will be no significant effect on soil nitrogen levels. The correct answer is that there will be "no effect on soil nitrogen."

**Final Answer**: If wheat field is inoculated with Rhizobium, there will be no effect on soil nitrogen.

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