CBSE Class 8 Science Crop Production and Management Worksheet Set A

A.Fill in the blanks

Question.Thecrops that are sown in the winter season are called __________.
Answer : Rabi crops

Question. The ploughed land is levelled with the help of___.
Answer : wooden planks or iron leveler

Question.The supply of water to plants at regulat intervals through sources other than rain is called ______.
Answer : irrigation

Question.The unwanted plants that grow along with the main crop in a field are called_______
Answer : Weeds 

Question._______ helps in the separation of grains from husk.
Answer : Winnowing 

Question.Plants of same kind grown at one place on a large scale is called a _____.
Answer : Crops

Question.Pesticides include rodenticides and________
Answer : insecticides 

Question.The process of transferring the seedlings from nurseries to fields is called ____
Answer : Transplantation 

Question. The science that deals with breeding ,feeding and caring of domestic animals is called ___-____
Answer : Animal husbandary

Question. Leguminous plants help in the replenishment of the soil with______
Answer : Nitrogen

ANSWER THE FOLLOWING QUESTIONS
B.Very short questions.

Question. What are the two methods of sowing seeds?
Answer : The two methods of sowing seeds are-
a. Broadcasting b. Seed drill

Question. Name two main modern methods of irrigation?
Answer : The two modern methods of irrigation are-
1. Drip irrigation 2. Sprinkler irrigation

Question. Name the machine that performs a dual job as harvester and a thresher?
Answer : A combine machine performs a dual job,as a harvester and a thresher

Question. Name two rabi crops.
Answer : Wheat & pea

Question. what is the first step for growing a crop?
Answer : The first step for growing a crop is preparation of soil.

Question. Name a common weedicide?
Answer : 2,4 D ( 2,4 dichlorophenoxy acetic acid).

Short Questions

Question. What is meant by agricultural implements?
Answer : The various tools needed during agricultural practices are called agricultural implements.eg. plough,hoe

Question. What is pisciculture?
Answer : The production of fish on a large scale by farming fish in fish nurseries is known as pisciculture.

Question. Why is it important to sow sow seeds at a correct distance from one another?
Answer : It is important to sow seeds at a correct distance from one another so that they get proper air , sunlight and nutrients.

Question. How does winnowing help in separation of grains from husk?
Answer : During winnowing heavier grains fall straight to the ground while the lighter husk and hay are blown a little farther away by the wind.

Question.Why is the spraying of pesticides harmful to us?
Answer : The spraying of pesticides is harmful to us because it can cause various harmful diseases.

Long Questions.

Question. (a) Why is irrigation necessary? (b) Why is the drip irrigation a water economic al method?
Answer : (a) Water is important for the survival of plants because of the following reasons-
i. Water is important for the proper growth and development of flowers fruits and seeds of plants.
ii. Water is essential for germination of seeds.
iii. Water is essential for carrying out the process of photosynthesis to make food.
iv. Water dissolves nutrients that are transport ed to each part of the plant.
v . Water also protects the crop from both frost and hot air currents.
(b) Drip irrigation is water economical method because in this irrigation system water falls drop by drop on the position of roots of the plant, thereby reducing both the consumption and loss of water

Question. What is hybridization ? How is it done in plants?
Answer : Hybridisation is a technique used for developing new varieties of crops by cross breeding two different varieties.
For hybridization , one plant is selected as male and the other one as female. The anthers of female plant are removed at the bud stage to prevent self pollination .This process is called emasculation. Thus , the pollens of male plant are dusted on the stigma of emasculated flower.Once the process of pollination is done the male and female gametes fuse and produce hybrid seeds that contain the characteristics of both male and female plants.

Question. (a)What is weedicides? (b) What are the harmful effects of weeds in the crop field?
Answer : (a)The Chemical substance which is used to control the growth of weeds is called weedicides.
ex-2,4-D(2,4-dichlorophenoxy acetic acid)
(b) The harmful effects of weeds in the crop field are.
i.The weeds spread crop pest and diseases by acting as alternate host to insects and microorganisms.
ii. weeds compete with the crop for nutrients, water , space , and light.
iii. Weeds reduce farm and forest productivity, they invade crops.
iv. Some weeds produce toxic substances that may be poisonous for animals and human beings.

To maintain the fertility of the soil following natural methods are used:
1.Field fallow: The land is left free or fallow for one or more seasons to naturally regain the nutrients.
2.Mixed cropping: It is the practice of growing two or more crops simultaneously on the same piece of field
3.Crop rotation: It is the process of growing different crops alternately on the same field.

Question. Differentiate between manure and fertilizer?
Answer : Fertiliers
i. It is an inorganic salt.
ii. It is prepared in factories.
iii. It does not add humus to the soil
iv. It is rich in plants nutrients like nitrogenand potassium
v. It is costly

Manure
i. It is a natural organic substance.
ii. It is prepared in fields by the decomposition of animal wastes,human wastes and plant residues.
iii. It provides a lot of humus to the soil.
iv. It contains less amount of essential plant nutrients.
v.It is cheap

              Questions

              Very Short Answer

Q1)       Why food has to be prepared on a large scale?

Q2)       What is tilling?

Q3)       What are crumbs?

Q4)       Define crop?

Q5)       Why paddy grown only in the rainy season?

             Short Answer

 Q6)       Define agriculture?

Q7)       Why do we have to eat food?

Q8)       Why we have to break crumbs in soil?

Q9)       Define agriculture implements?

Q10)     Distinguish between farming and agriculture?

            Long Answer

Q11)     State the difference between kharif crops and rabi crops?

Q12)     Write short note of levelling of soil?

Q13)     Explain about agricultural practices?

Q14)     Write short note on cultivation crops?

Q15)     Explain about agricultural implements?