CLASS 8 SCIENCE -CROP PRODUCTION AND MANAGEMENT

1. ………….. crop is harvested in october.
2. The kind of crop grown only for sale profit is ………….
3. …………. is used to till the soil in agriculture.
4. In …………. type of irrigation, water is sprayed on the plants using rotating sprinkler.
5. Threshing can be done using the machine………….
6. Large grasses cultivated for their nutritious seeds are called…………..
7. Preparation of soil involves ……………. and …………….. it.



8. The agricultural implement used to sow seeds is called …………..
9. Allowing a field to remain free of crops for one or more seasons is called field………….. it allows the field to regain…………..
10. ……………. Bacteria fixed nitrogen in root nodules of leguminous plants.
11. The practice of growing fruit, vegetables, flowers and ornamental plant is called ……..
12. Removing the chaff from the grain is called………….
13. The method of irrigation in which emitters let out a trickle of water near the roots is called…………
14. Two plantation crops are…………. and…………….
15. Farmer’s friend……………
16. Practice questions:
    Question 5. Differentiate between kharif and rabi crops with two example of each?
    Question 6. How is lavelling different from tilling and write the significance of these processes?
    Question 7. What are weeds and how do weed affect crops?
    Question 8. What is hybridization?
    Question 9. Explain nitrogen cycle?
    Question 10. What is nitrogen assimilation?
    Question 11. What is animal husbandry?
    Question 12. List the steps involved in crop production?
    Question 13. What are the advantages of ploughing the soil before sowing seeds?
17. LEARN THE QUESTIONS GIVEN BELOW

Question 1.

Name one pesticide you will use to kill insects that harm crops?

Answer

BHC (gammaxane)

Question 2.

Name three natural methods of adding nutrients to soil?

Answer

Field fallow, crop rotation and mixed cropping

Question 3.

Why should grains be dried before storage?

Answer

Grains have to be dried to prevent the growth of microorganisms before storage.

Question 4.

Why is it not advisable to sow rice in winter season in our country?

Answer

Because they need more water to grow.

Question 5.

If soil has all the nutrients, why do we need to replenish it?

Answer

when crops are grown in fields year after year, the soil becomes deficient in nutrients and less fertile. So, the soil has to be replenished with its lost nutrients from time to time.

Question 6.

Why is it important to sow seed at the correct depth and distance?

Answer

Seeds must be sown at the correct depth in the soil. If they are sown too deep, they may not grew due to the lack of air. And if they are sown too close to the surface, birds can eat them.

Question 1. How would you prepare youR field before sowing seeds?

Answer

Preparation of soil involves ploughing and lEvelling it. Ploughing involves loosening and turning of soil using a tool or an implement called the plough made up of wood or iron. They are either drawn by bullocks or by tractors. The ploughed soil often has crumbs of soil that need to be crushed and the soil lavelled. This is achieved using a leveller.

Question 2. Why is it essential to irrigate our fields?

Answer

A good crop yield requires availability of the right amount of water. Minerals and fertilizers can only be absorbed by the plants in presence of water. Seeds do not germinate in the absence or scarcity of water. Hence, agricultural fields needs to be irrigated or watered regularly.

Question 3. Compare the benefits and disadvantages of using manures and fertilizers in the crop field?

Answer

table for question

Question 4. Why continuous plantation of the same crop in the field should be avoided?

Answer

Different cops have different nutrient requirements. If you grow the same crop in the same field season after season, the soil becomes deficient in the set of nutrients needed by the crop. So it is better to grow one crop in one season and another crop in the next season. This is done by crop rotation method.

Question 1. How would you prepare yous field before sowing seeds?

Answer

Preparation of soil involves ploughing and lavelling it. Ploughing involves loosening and turning of soil using a tool or an implement called the plough made up of wood or iron. They are either drawn by bullocks or by tractors. The ploughed soil often has crumbs of soil that need to be crushed and the soil lavelled. This is achieved using a leveller.

Question 2. Why is it essential to irrigate our fields?

Answer

A good crop yield requires availability of the right amount of water. Minerals and fertilizers can only be absorbed by the plants in presence of water. Seeds do not germinate in the absence or scarcity of water. Hence, agricultural fields needs to be irrigated or watered regularly.

Question 3. Compare the benefits and disadvantages of using manures and fertilizers in the crop field?

Answer DO IT YOURSELF

table for question

Question 4. Why continuous plantation of the same crop in the field should be avoided?

Answer

Different cops have different nutrient requirements. If you grow the same crop in the same field season after season, the soil becomes deficient in the set of nutrients needed by the crop. So it is better to grow one crop in one season and another crop in the next season. This is done by crop rotation method.