NCERT SOLUTION OF CLASS 8th SCIENCE CHAPTER -1

Crop production and management

      Exercise solved

Q1: select the correct word from the following list and fill in the blanks .float, water, crop, nutrients, and preparation.

(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, water and nutrients.

Q2: match items in Column A with those in column B

             Column A                 Column B
(I)  Kharif crops (A) paddy for cattle. 
(II) Rabi crops  (b) Urea and super phosphate.
(III)  chemical fertilizers (c) Animal excreta, cow dung, urine and plant waste. 
(IV) organic manure (d) Wheat, gram, pea. (e) paddy and maize 

Answers:

  (I) –  (e) Paddy and maize

 (II)  – (d) Wheat, gram, pea.

 (iii) – (b) Urea and super phosphate.

 (IV) – (c) Animal excreta, cow dung, urine and plant waste.  (A) paddy for cattle. 

Q3: give two examples of each:

(a)  Kharif crop   (b) Rabi crop

Answers:

(A)  Kharif crop ;- Paddy and maize.

(B) Rabi crop ;-Wheat and gram.

Q4: write a paragraph in your own words on each of the   Following:

(A) Preparation of soil

(B) Sowing

(C) Weeding

(D) Threshing

Answers:

(A) Preparation of soil: We should prepare the soil first to loosen the soil to make the plants root breath.

(B) Sowing: After preparation of soil. It is ready for sowing of seeds. Healthy and clean seeds should be selected. Sowing is done by seed drill or funnel shaped tools.

(C) Weeding: The unwanted pants that grow along with main crop are called weeds. The process of removal of these weeds is known as weeding.

(D) Threshing: In the harvested crop to separate the grains from the crop. This process is called threshing.

Q5: explain how fertilizers are different from manure.

Answers:

Fertilizers Manure
(I) these are chemical substances. (A)These are natural substances.
(II)They are made in factories. (B)They are made in field.
(III)They are rich in a particular nutrient. (C)They Contains a nutrients that human body requires.
(IV)They don’t provide humus to the soil. (D)They provide humus to soil.

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

Answers:

The process of watering plants at different interval of time is known as irrigation.

Two methods of irrigation are:

(I)Sprinkler system: The process of providing water to the crop by the pipes that have tiny holes at particular distance in them and their nozzles move in all direction to all crops.

(II)Drip system:

  This Process also conserves water, in this process the water is supplied to the roots of the plant drop by drop.

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

Answers:

Wheat does not require huge amount of water for growth. In country to it; in Kharif season, otherwise, excess water may destroy the crop.

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

Answers:

Plantation of crops in a field, continuously for many years can make the soil infertile lose its nutrients does not get the time to replenish them.     

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

Answers:

The weeds are unwanted plants grown with the main crop which compete with the crop for water, nutrients and sunlight.   It can be removed from khurpi, plough etc or using chemicals like 2;4D. These chemicals are called wedicides and the process of removal of weeds is called weeding.

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

1 : 2 ; 3

ENDING CROP TO SUGAR FACTORY  ;   IRRIGATION ;   HARVESTING :

4 : 5 ; 6:

SOWING : PREPARATION OF SOIL : PLOUGHING THE FIELD :

7

MANURING

Answers:

PREPARATION OF SOIL : PLOUGHING THE FIELD : SOWING

5 ; 6 ; 4

MANURING ; IRRIGATION ;    HARVESTING

7 : 2 ; 3;

SENDING CROP TO SUGAR FACTORY

1

Post Author: Seema Gupta