CROP PRODUCTION AND MANAGEMENT (CLASS 8, SCIENCE)

Crops

Earlier, man was basically a hunter collecting food from forest. In those days, human beings consumed plant parts and animals without cooking. When these early humans settled at different places, they started growing plants for food. Slowly, this activity became systematic and began to take place on a large-scale.

The practice of growing plants at a place is known as agriculture.

**Plants grown for food on a large-scale are known as crops.

**Crops are categorized on the basis of the growing season as follows:

• Kharif crops − They include crops like rice, maize, soyabean, groundnut etc, which are grown in the rainy season (during June-September.) They are dependent on South-Western monsoons.

**• Rabi crops − They include crops like wheat, gram, pea, mustard etc., which are grown in the winter season (during October-March.) They are not dependent on monsoons

(**Curiosity Corner:

Have you heard about hybrid seeds? Do you know what they are?

Hybrid seeds are the type of seeds which have the characters of two different plants. Hybrid seeds are obtained by the process of hybridization. Hybridisation is the process by which two dissimilar plants with desired characteristics are mated or crossed. The resultant plant will have the characteristics of both the parent plants.

This is very easy to understand through the given pictorial representation.

**(Green Revolution: It is a programme started in the 1960s to increase the agricultural productivity by the use of improved seeds and advanced agricultural technologies.)

**Organic Farming

Organic farming is the practice of cultivating crops without the use chemical fertilisers, weedicides or pesticides. As awareness regarding harmful effects of using chemical fertilisers or pesticides is increasing, the organic farming is slowly gaining popularity among the cultivators. Farmers are now using organic manure, made from animal and plant wastes, to provide supplements to the soil. Practices like crop rotation, mixed cropping, inter cropping, hand weeding, etc are also used.

Roof Top Gardening
Roof top gardening has emerged as a new trend for urban households who do not have much space for outdoor gardening. Roof tops can be used for growing plants of various types such as, ornamental plants, vegetables, fruits, etc. but certain precautionary measures are required.

**Basic Practises of Crop Production

Cultivation of crops involves several agricultural practises, which are undertaken by farmers over a period of time.

Major practices included in agriculture are as follows:

The basic steps given above for the crop production do not always occur in the same series. The water requirements of different crops are different but as the plants require a regular supply of water, irrigation of crops is carried out on a regular basis. Hence, irrigation is a continuous process, until the crops are ready for harvesting. Most farmers irrigate their crops before or after the application of manures and fertilisers as water makes the nutrients in the manures and fertilisers easily available to the plants.

**Importance of Manures and Fertilisers

Do you know what manures and fertilisers are?

Manures and fertilisers are substances, which are added to soil to increase the nutrient content of soil for the healthy growth of plants.

Manures

Manures are the decomposed, organic matter. These include cattle dung, oil cakes, vegetable wastes etc. These animal or plant wastes are decomposed by micro-organisms such as bacteria and fungi. This decomposed matter is used as manure. It contains essential nutrients required by plants for their growth.

Manuring is advantageous because it:

• improves soil texture

• improves water retaining capacity of soil

• replenishes soil with nutrients

• increases the number of useful micro-organisms in soil

Fertilisers help farmers obtain a better yield of crops. But, then why is the use of chemical fertilisers not encouraged? This is because they have a number of disadvantages.

• These fertilisers can enter water bodies through runoff water and cause water pollution.

• The fertilisers in the water can also enter the body of humans through food chain and can be harmful to human health.

• Excessive use of fertilisers can reduce the natural replenishing ability of soil.

• Excessive use of fertilisers can change the chemical nature of soil and make it less fertile.

Let us take a look at the table given below to study the differences between fertilisers and manures.

Fertilisers	Manures
1. They are inorganic salts. 2. They are manufactured in factories. 3. They do not add any humus to soil. 4. They are rich in plant nutrients like nitrogen, phosphorus, potassium, etc.	1. They are natural substances made from decomposed residue of plant and animal wastes. 2. They are prepared in fields. 3. They add humus to soil. 4. They have a relatively poor content of plant nutrients.

Irrigation is the practice of supplying water to crops through canals, wells, and waterways. The amount of water supplied to crops is extremely important as excess water can also damage crops.

Modern methods of irrigation

Modern methods of irrigation help save water. They include:

 

Uncultivated and undesired plants, which grow at any place and utilize the space, water, and nutrients of that area, are known as weeds. Corn cockle, Agrostemma, Oxalis, Plantago etc. are names of some common weeds.

Weeding is the process of removing weeds from fields.

Why are weeds unwanted and unrequired?

• Weeds compete with crops for nutrients, water, and space. Thus, they can reduce the crop yield.

• They can interfere in the process of harvesting.

• Some weeds can be poisonous for human beings and other animals.

Methods of Storage

The produce, which is harvested, needs to be stored safely to prevent it from getting eaten by pests and rodents. Therefore, farmers employ a number of storage methods to protect their produce and prevent it from getting spoilt. Let us explore these methods in detail.

• Farmers sun-dry their seeds before storing them to reduce moisture in them. This protects the grains from insect pests, bacteria, and fungi.

• Farmers store grains in jute bags or metallic bins. Granaries and silos are used for large-scale storage of grains. This protects the grains from pests like insects and rodents.

• Dried neem leaves are also used for storing grains at home. On a larger-scale, certain chemicals are used to protect the grains from pests and micro-organisms.

 

Food from Animals

You know that animals provide us different types of food products like plants. For this purpose, animals are reared in farms or homes, and are provided with proper food, shelter, and care.

The science of rearing animals for a commercial purpose is known as animal husbandry.

Let us take a look at the table given below to find out about the food products obtained from animals.

Apart from the food materials, animals are also used for many other purposes. They give us leather, wool and many more things. Let’s see through this video how much we are dependent on animals for our various requirements.

Curiosity Corner What animals did the ancient Egyptian farmers have? Animals were very important to ancient Egyptian farmers. Animals helped them with farming tasks such as separation of seeds from chaff, pulling the plough, eating unwanted grain or wheat and providing the Egyptians with food and drink. They kept animals such as cattle, goats, pigs, ducks, cows, and geese.