A wheat field is inoculated with bacterium Azotobacter. Choose the correct option(s) as a result of inoculation.
(A) The soil will get enriched in potassium
(B) The soil will get enriched in nitrogen
(C) There will be no effect on soil fertility
(D) Wheat production will increase
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (B) and (D) only
(A) The soil will get enriched in potassium — False. Azotobacter fixes nitrogen, not potassium.
(B) The soil will get enriched in nitrogen — True. It fixes atmospheric nitrogen while free-living in soil.
(C) There will be no effect on soil fertility — False. Added nitrogen raises fertility.
(D) Wheat production will increase — True. More nitrogen helps the crop grow.
NCERT Extract:
Microbes as Biofertilisers – “… You have studied about the nodules on the roots of leguminous plants formed by the symbiotic association of Rhizobium. These bacteria fix atmospheric nitrogen into organic forms, which is used by the plant as nutrient. Other bacteria can fix atmospheric nitrogen while free-living in the soil (examples Azospirillum and Azotobacter), thus enriching the nitrogen content of the soil.”