NCERT Solutions for Class 8 Science Chapter 1 Crop Production And Management

Q1. Select the correct word from 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.

Answer:

(a) The same kind of plants grown and cultivated on a large scale at a place is called crop.

(b) The first step before growing crops is preparation of the soil.

(c) Damaged seeds would float on top of water.

(d) For growing a crop, sufficient sunlight and water and nutrients from the soil are essential.

Q2. Match items in column A with those in column B.

A B
(i) Kharif crops (a) Food for cattle
(ii) Rabi crops (b) Urea and super phosphate
(iii) Chemical fertilisers (c) Animal excreta, cow dung urine and plant waste
(iv) Organic manure (d) Wheat, gram, pea
(e) Paddy and maize

Answer:

Matched items of column A with column B:

NCERT Solutions for Class 8 Science Chapter 1 Crop Production and Management:

Q3. Give two examples of each:

(a) Kharif crop:

Answer:

Kharif Crop : The crops which are sown in the rainy season are called kharif crops. The rainy season in India is generally from June to September. Ex: Paddy, maize, soyabean, groundnut and cotton are kharif crops.

Q3. Give two examples of each (b) Rabi crop

Answer:

Rabi Crops : The crops grown in the winter season (October to March) are called rabi crops. Examples of rabi crops are wheat, gram, pea, mustard and linseed.

Q4 . Write a paragraph in your own words on-

(a)Preparation of soil

Answer:

The preparation of the soil is the first step before growing a crop. It is to turn the soil and loosen it. This allows the roots to penetrate deep into the soil. The loose soil allows the roots to breathe easily even when they go deep into the soil. The loosened soil helps in the growth of earthworms and microbes present in the soil. These organisms further turn and loosen the soil and add humus to it. In this way, various nutrients in the dead organisms are released back into the soil. These nutrients are again absorbed by plants.

Since only a few centimeters of the top layer of soil supports plant growth, turning and loosening of soil brings the nutrient-rich soil to the top so that plants can use these nutrients. Thus, turning and loosening of soil is very important for the cultivation of the crop.

The process of loosening and turning of the soil is called tilling or ploughing. This is done by using a plough.

Q4. Write a paragraph in your own words on-

(b) Sowing

Answer:

Sowing is an important part of crop production. Before sowing, good quality, clean and healthy seeds of a good variety-are selected. Farmers prefer to use seeds which give a high yield. It is placing of seed in the soil with the help of some tools.

Some tools like funnel-shaped which was used traditionally or modern tools like seed drill which sows the seeds uniformly at equal distance and depth save time and labor.

Q4. Write a paragraph in your own words on

(c)Weeding

Answer:

The removal of weeds is called weeding. Weeding is necessary since weeds compete with the crop plants for water, nutrients, space, and light. Thus, they affect the growth of the crop. Some weeds interfere even in harvesting and may be poisonous for animals and human beings.

Tilling before sowing of crops helps in uprooting and killing of weeds, which may then dry up and get mixed with the soil. Weeds are also controlled by using certain chemicals, called weedicides, like 2,4-D. These are sprayed in the fields to kill the weeds. They do not damage the crops

Q4. Write a paragraph in your own words on-

(d)Threshing

Answer:

In the harvested crop, the grain seeds need to be separated from the chaff. This process is called threshing. This is carried out with the help of a machine called ‘combine’ which is, in fact, a harvester as well as a thresher.

Farmers with small holdings of land do the separation of grain and chaff by winnowing

Solutions for NCERT class 8 science chapter 1 crop production and management:

Q5. Explain how fertilisers are different from manure.

Answer:

Fertilisers are different from manures in the following ways:

Q6. What is irrigation? Describe two methods of irrigation which conserve water.

Answer:

The supply of water to crops at regular intervals is called irrigation .

Two methods of irrigation which conserve water are:

(i) Sprinkler system : The perpendicular pipes, having rotating nozzles on top, are joined to the main pipeline at regular intervals. When water is allowed to flow through the main pipe under pressure with the help of a pump, it escapes from the rotating nozzles. It gets sprinkled on the crop as if it is raining.

(ii) Drip system : the water falls drop by drop directly near the roots. So it is called the drip system. Water is not wasted at all. It is a boon in regions where the availability of water is poor.

Q7. If wheat is sown in the kharif season, what would happen? Discuss.

Answer:

If wheat is sown in the kharif season, then the whole crop will get destroyed because of many damaging factors like not getting cold temperature, getting unnecessary rainwater, humidity, etc. as a result wheat crop won't be able to grow.

Q8. Explain how soil gets affected by the continuous plantation of crops in a field.

Answer:

The continuous plantation of crops in a field decreases the number of nutrients present in the soil which are helpful for the proper growth and functioning of the plants. Hence decreasing the fertility and also yield of the crop.

NCERT solutions for class 8 science chapter 1 crop production and management:

Q9. What are weeds? How can we control them?

Answer:

In a field, many other undesirable plants may grow naturally along with the crop. These undesirable plants are called weeds.

We can control them by the following steps:

(i) Chemical like weedicides is sprayed in the fields to control the weeds.

(ii) Or by manual removal by uprooting or cutting them close to the ground with the help of khurpi.

Q10. Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.

Answer:

Flow chart of sugarcane crop production arranged boxes shown below:

Q11. Complete the following word puzzle with the help of clues given below.

Down

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.

Answer:

Given below is solved puzzle: