Class 12th Biology 2018 Set1 Delhi Board Paper Solution
Question 6
Your advice is sought to improve the nitrogen content of the soil to be used for cultivation of a non-leguminous terrestrial crop.
(a) Recommend two microbes that can enrich the soil with nitrogen.
(b) Why do leguminous crops not require such enrichment of the soil?
Answer
(A) Two microbes which can enrich the soil with nitrogen are Nostoc and Azospirillium.
(B) Leguminous plants contain rhizobium bacteria in their root nodules. These bacteria convert atmospheric nitrogen to a form which can be used by plants. This decreases nitrogen deficiency in the soil and makes it fertile.
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