Question

What will happen if a wheat field is inoculated with bacterium Rhizobium?

• A. The soil will become rich in calcium.
• B. The soil will become rich in nitrogen.
• C. There will be no effect on soil nitrogen.
• D. The soil will be rich in O${}_2$.

Answer 1

The correct option is C There will be no effect on soil nitrogen.

Rhizobium is microaerobic rod-shaped bacteria, which increases soil fertility by fixing atmospheric nitrogen in root nodules of legumes. If Rhizobium is inoculated in the wheat field, they won't be able to infect wheat plants and form root nodules as wheat is not a leguminous plant. Consequently, soil fertility will not change.

Thus, the correct answer is option A.