NCERT Solutions for Class 8 Science Chapter 1 Crop Production and Management
1.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.
2.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 superphosphate |
(iii) Chemical fertilisers | (c) Animal excreta, cow dung urine and plant wastes |
(iv) Organic manure | (d) Wheat, gram, pea |
(e) Paddy and maize |
Answer:-
A | B |
(i) Kharif crops | (e) Paddy and maize |
(ii) Rabi crops | (d) Wheat, gram, pea |
(iii) Chemical fertilisers | (b) Urea and superphosphate |
(iv) Organic manure | (c) Animal excreta, cow dung urine and plant wastes |
3.Give two examples of each.
(a) Kharif crop
(b) Rabi crop
Answer:-
(a) Kharif crop :- Paddy and maize.
(b) Rabi crop :- Wheat and gram.
4.Write a paragraph in your own words on each of the following.
(a) Preparation of soil (b) Sowing
(c) Weeding (d) Threshing
Answer :- Preparation of soil:- Preparation of soil is the most necessary step before growing a crop. It involves tilling and loosening of the soil. This allows the roots to penetrate deep in the soil and to breath easily even when they are deep in the soil.
(b) Sowing:- The process of putting seeds into the soil is called sowing. First of all seeds of a good variety are selected and then sowing is done by either traditional methods or by using equipment’s seed drill.
c) Weeding :-Removal of unnecessary plants from the field is called weeding. There are many way to remove weeds Tilling before sowing of crops, physical removal of weeds by uprooting or cutting them close to the ground, using certain chemicals called weedicides etc.
(d) Threshing:- The process of separating the grain seeds from the chaff is called threshing.
5. Explain how fertilisers are different from manure.
Answer:-
6. 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 following:-
(i) Sprinkler irrigation system: Sprinkler irrigation system releases water similar to rainfall. It has an arrangement of vertical pipes with rotating nozzles on the top. It is more useful in the uneven and sandy land where sufficient water is not available.
(ii) Drip irrigation system: It involves dripping water onto the soil at very low rates. In this system has pipes or tubes with very small holes water plants drop by drop just at the base of the root. It is very efficient as water is not wasted in it.
7. If wheat is sown in the kharif season, what would happen? Discuss.
Answer:- Wheat is a rabi crop and it requires less amount of water to grow. If wheat is sown in the kharif season then it would get destroy due to excess supply of water.
8. Explain how soil gets affected by the continuous plantation of crops in a field.
Answer:- Plants require many nutrients from the soil for their growth. Continuous plantation of crops results in deterioration of certain nutrients. As the results soil becomes infertile hence there should be a enough time to replenish the nutrients between crops in order to get a good yield.
9. What are weeds? How can we control them?
Answer:- The undesirable plants are called weeds. Weeds can be controlled by methods called weeding. Tilling of soil before sowing of crops helps in uprooting and killing of weeds, weeds can also be controlled by using certain chemicals, called weedicides.
10. Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.
Answer:-
11.Complete the following word puzzle with the help of clues given below.
Down
- Providing water to the crops.
- Keeping crop grains for a long time under proper conditions.
- Certain plants of the same kind grown on a large scale.
Across
- A machine used for cutting the matured crop.
- A rabi crop that is also one of the pulses.
- A process of separating the grain from chaff.
Answer:-
