Question

In a classroom discussion, three students made the following statements.
Shikha: Fertilizers are chemical substances that are rich in a particular nutrient.
Ritesh: Fertilizers increase the water holding capacity of the soil.
Abhishek: Fertilizers used in excess provide lots of humus to the soil.
Which student(s) made incorrect statement(s) ?
A) Shikha and Ritesh
B) Ritesh and Abhishek
C) Abhishek and Shikha
D) Shikha only

Answer 1

Hint: Fertilizers are the chemical substances that are used in agricultural fields to increase the yield of crop. These fertilizers contain the essential nutrients that are vital for the growth of plants which are nitrogen, phosphorus and potassium i.e. NPK.

Complete answer:
 We all are very well aware that to grow crops commercially, fertilizers play a major role. These are used by the farmers to increase the crop yield as well as the fertility of the land. With the help of fertilizers the crops look healthier and in a better condition. These are also helpful in reducing the growth time of the crop i.e. they grow much faster.

Advantages of fertilizers:
- They are very convenient to carry, store as well as apply.
- They are water soluble and so easily dissolve in soil which means are easily absorbed by the plants.
- They have an immediate impact on the plants and so are very necessary for commercial crops.

Disadvantages of fertilizers:
- They are too expensive and so the small farmers cannot afford it.
- Its long term use decreases the microbial activity leading to the disturbance of ph in the soil.
- Leads to leaching due to which fertilizers reach the river causing eutrophication.

From the above discussion, we know that option (B) is our right answer.

Note: Though there are many harmful impacts of fertilizers still they do possess some important too like due to fertilizers the plants develop an increased level of tolerance towards the plants. This has helped the plants to not rely upon insecticides and herbicides making the plants healthier.