Class 7 Science Chapter 1 Question Answers - Crop Production and Management

Q1: What are weedicides? Give some examples.
Ans: Weedicides are the chemicals that are used to remove weeds. Some commonly used weedicides are 2, 4-D and metachlor.

Q2: What is a crop?
Ans: Crop is the term used to describe a plant that is grown in a field on a large scale. For example, cereal crops, wheat crops.

Q3: What is a plough?
Ans: A plough is an equipment for ploughing. It is mainly made of a wooden shaft called a plough-shaft, attached to a triangular iron blade called ploughshare.

Q4: What do you mean by produce?
Ans: The products obtained from the crops are called produce.

Q5: What do you mean by the term agricultural practice?
Ans: Agricultural practices are those practices which involve the necessary steps to be taken during production of crops.

Q6: What are the advantages of levelling?
Ans: Following are the advantages of levelling:

• Levelling helps to prevent soil erosion caused by wind or air.
• It helps in sowing the seeds uniformly, and thus helps the plants to grow uniformly too.
• It helps in proper irrigation by allowing the water to get distributed uniformly throughout the soil.

Q7: What is a cultivator?
Ans: Cultivator is a farm implement used for stirring and pulverizing the soil for planting crops.

Q8: What is a transplant?
Ans: Some of the crops are first grown in the nurseries and then transferred to the main field. This process is known as transplantation.

Q9: Explain the term levelling.
Ans: Levelling is the process of breaking down the larger lumps of soil, and then levelling them by using a leveller.

Q10: What are the advantages of manure?
Ans: Following are some advantages of manure:

• It enhances water-holding capacity of soil.
• It improves soil quality.
• It promotes the growth of soil friendly microbes.
• It is renewable, biodegradable and eco-friendly.

Q11: Write short note on the terms:
(i) Storage
(ii) Harvesting
Ans: 

• Storage: Storage of produce is an important task. If the crop grains are to be kept for longer time, they should be safe from moisture, insects, rats and microorganisms. Before storing, the grains are properly dried in the sun to reduce the moisture in them. This prevents the attack by insect pests, bacteria and fungi. Grains are stored by farmers in jute bags or metallic bins. However, large scale storage of grains is done in silos and granaries to protect them from pests like rats and insects.
• Harvesting: After maturation of crop, harvesting is an important task. In harvesting, crops are pulled out or cut close to the ground. It usually takes 3 to 4 months for a cereal crop to mature. Harvesting in our country is either done manually by sickle or by machine called harvester.

Q12: What is irrigation? Name the two main methods of irrigation and define them briefly.
Ans: The artificial method of watering the plants for assisting in the growth of the plants is called irrigation. The two main methods of irrigation are:

• Traditional method: The traditional method of irrigation is very less expensive and they often lead to wastage of water. Traditional method of irrigation involves chain pump, dhekli, moat (the pulley system) and rahat (lever system).
• Modern method: Modern methods of irrigation are more inclined towards the use of diesel, bio¬gas, solar energy and electricity for lifting water.

The two most important modern system of irrigation are:

• Sprinkler irrigation system
• Drip irrigation system

Q13: What is ploughing or tilling? State its advantages.
Ans: The process of loosening and turning of the soil is called tilling or ploughing. This is done by using a plough. Ploughs are made of wood or iron.
Following are the advantages of ploughing or tilling:

• Ploughing loosens the soil and makes it aerated.
• It helps in mixing organic matter with the soil uniformly.
• It initiates the growth of natural agents and microorganisms and thus, keeps the soil fertile.
• It increases the water holding capacity of soil.
• It helps in easy penetration of root into the soil.

Q14: What do you mean by the term crop? Explain briefly the types of crops.
Ans: 

• Crop is the term used to describe a plant that is grown in a field on a large scale. For example, cereal crops, pulses and fruit crops.
• The crops grown in India can be classified as kharif and rabi.
• Kharif crops are sown in the rainy season by June/July and are harvested by September/October. Thus they are also known as summer season crops. For example, rice, maize, etc.
• Rabi crops are sown in the winter season in October or November and are harvested by March/April. Thus, they are also called winter season crops. For example, mustard, wheat, potato, etc.

Q15: Define the term agricultural practices and also state the important steps taken during crop production.
Ans: Agricultural practices are those practices which involves the necessary steps to be taken during production of crops. There are number of steps of crop production which are to be done very carefully to ensure that crops get produced timely.
Some of the most important steps taken during crop production are as under:

• Soil preparation
• Sowing
• Adding manure and fertilisers
• Irrigation
• Weeding
• Harvesting
• Threshing and winnowing
• Storage of grains

Q16: What do you mean by weeding? Why the process of weeding necessary? Name the methods applied for weeding.
Ans: The undesirable plants that grow among the crops are called weeds. The process of removing these weeds is known as weeding. Weeds compete with the crop plants for nutrients and space. They grow much rapidly than the crop plant. So weeding is necessary.
Methods applied for weeding are as follows:

• Manual method: Manual method of removing weeds is the most time consuming method. In this system weeds are controlled by hand pulling, digging, shallow tillage, etc., by using certain implements like khurpi, hoe, etc.
• Chemical method: In this method chemicals called, weedicides are used to remove weeds. For example, metachlor and 2, 4-D.
• Biological control method: This method is the most commonly used method of weed control. It involves the use of some specific insects that destroy the growth of some specific weeds. For example, leafy spurge, a weed, is controlled by using flea beetles.