Crop Production and Management (Biology) Class 8 - NCERT Questions

Q 1.

Select the correct word form the following list and fill in the blanks. float, water, crop, nutrients, preparation
(A) The same kind of plants grown and cultivated on a large scale at a place is called ______.
(B) The first step before growing crops is __________ of the soil.
(C) Damaged seeds would __________ on top of water.
(D) For growing a crop, sufficient sunlight and __________ and __________from the soil are essential.


(A) crop (B) preparation (C) float (D) water, nutrients.

Q 2.

Match items in Column A with those in Column B.


Q 3.

Give two examples of each
(A) Kharif crop
(B) Rabi crop.


(A) Paddy and maize
(B) Wheat and gram.

Q 4.

Write a paragraph in your own words on each of the following:
(A) Preparation of soil
(B) Sowing
(C) Weeding
(D) Threshing


(A) Preparation of soil: Preparation of the soil involves loosening and turning it. This has the following advantages:
(i) Loose soil has a lot of air trapped in it, which is used by the roots to breathe easily.
(ii) Loose soil helps the growth of earthworms and microbes in the soil. They provide nutrients to the soil and aid in further loosening of the soil.
(iii) Turning and loosening of soil brings nutrient-rich soil to the top. Plants can then absorb these nutrients more efficiently.
The process of loosening and turning the soil is called tilling or ploughing. It is carried out by using a wooden or iron plough which is pulled either by animals or by tractor.
(B) Sowing: Putting seeds in soil is called sowing. While sowing seeds, following points should be kept in mind:
(i) Seeds should be of good quality, healthy and free from diseases.
(ii) They must be planted at the proper depth in the soil.
(iii) Seeds require water for germination. The soil should, therefore, have water in it.
(iv) Seeds should be sown at proper distances. Seeds can be sown manually or with the help of seed drill.
(C) Weeding: The unwanted plants in the crops are called weeds. These weeds absorb the nutrients from the soil. So it is necessary to remove them. Weeds are either removed manually or by mechanical tools. The process of removal of weeds is called weeding. Some chemicals like 2, 4–D are also used to kill the weeds.
(D) Threshing: Process of separation of grains from the crop is called threshing. It can be done manually by making oxen or buffaloes trample over the cut crop or it can be done by a machine called thresher.

Q 5.

Explain how fertilizers are different from manures.


Differences between manures and fertilizers are as following:

Q 6.

What is irrigation? Describe two methods of irrigation which conserve water.


The process of watering the crops is called irrigation.
Two methods of irrigation are:
(i) Sprinkler system : This system is used on the uneven land where less water is available. The perpendicular pipes, having rotating nozzles on top, are joined to the main pipeline at regular intervals. Water is allowed to flow through main pipe under pressure, which escapes from the rotating nozzles. In this way water gets sprinkled on the crop.
(ii) Drip irrigation: This system is used to save water as it allows the water to flow drop by drop at the roots of the plants. It is the best technique for watering fruit plants, gardens and trees. Water is not wasted at all.

Q 7.

If wheat is sown in the kharif season, what would happen? Discuss.


Wheat crop does not require much water to grow, so wheat would not grow in kharif season. The seeds would get destroyed in excess water due to rainy season.

Q 8.

Explain how soil gets affected by the continuous plantation of crops in a field.


If we sow crops continuously in a field then the lack of specific nutrients takes place in the soil. The field becomes unfertile. It does not give any time to soil to replenish the nutrients. Thus, the soil is unable to sustain any further healthy and good crop.

Q 9.

What are weeds? How can we control them?


Weeds are unwanted plants. They grow with crops and compete for nutrients and water with main crop. So weeds are very harmful. Process of controlling the weed is called weeding. Weeding is done manually by using khurpi and by using mechanical machines. Weeds are also controlled by using some chemical substances like 2, 4-D. These chemicals are called weedicides and are used to kill and destroy the weeds.

Q 10.

Arrange the following boxes in proper order to make a flow chart of sugar cane crop production.


Q 11.

Complete the following word puzzle with the help of clues given below.
(1) Providing water to the crops.
(2) Keeping crop grains for a long time under proper conditions.
(5) Certain plants of the same kind grown on a large scale.
Across (→)
(3) A machine used for cutting the matured crop.
(4) A rabi crop that is also one of the pulses.
(6) A process of separating the grain from chaff.