Question

A few gram seeds were placed in each of the three pots A, B and C containing soil. The soil in Pot A is mixed some green twigs and leaves. The soil in pot B is mixed with old cow dung while soil of pot C is mixed with urea. Pots are watered regularly. Which of the following will be observed after 10 days?

• A. Lot of growth in A
• B. Not much growth in B
• C. Lot of growth in B but very little growth in C
• D. Very little growth in A but lot of growth in B and C

Answer 1

Answer: (D)

Very little growth in A but lot of growth in B and C

Manure is an organic substance produced by the decomposition of plant and animal wastes in the presence of microorganism and used as fertilizers. Thus, the fresh manure contains decomposing bacteria along with active digestive enzymes. These enzymes contribute to the faster heating of the manure which accelerates the decomposition of organic materials by the soil microorganisms. The end result of better decomposition of organic material is faster nutrient release to the plant. When urea is placed on the surface of the soil, a chemical reaction takes place that changes the urea to ammonium bicarbonate. Urea should be mixed in with the soil for maximum effectiveness. For plants that love acidic soils, urea is one of the top fertilizers for acidifying soils. Hence, seeds will grow most in pots B and C.