Question

Plant can not use the nitrogen present in the soil directly why

Answer 1

Plants do not use nitrogen directly from the air because nitrogen is noble gas and is unreactive, and cannot be used by green plants to make protein. Nitrogen gas therefore, needs to be converted into nitrate compound in the soil by nitrogen-fixing bacteria in soil, root nodules so that plants can use it.

Answer 2

Answer:

A plant can not use atmospheric nitrogen directly because it is present in free gaseous form in the atmosphere whereas plants are capable of absorbing N2 in the form of Nitrogen compounds like Nitrites and nitrates only from the soil, which is converted by the microorganisms in the soil.

Explanation:

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