Plants can make their food themselves whereas animals including humans cannot make their own food.
Humans get their food from plants, or animals, or both.
In order to provide food for a large population we need to adopt certain agricultural practices.
Evolution of Crop Production or Agriculture
Till 10,000 B.C.E. people were nomadic, wandering in groups from place to place in search of food and shelter, eating raw fruits and vegetables and hunting animals for food. Later, they started cultivating land and produced rice, wheat and other food crops.
What is a crop?
Plants of the same kind that are cultivated at one place on a large scale is called a crop.
Ex: A Wheat Crop – here all the plants grown in a field are wheat.
Crops Classification
Crops (cereals, vegetables and fruits)are classified on the basis of the season in which they grow into:
Basic Practices of CropProduction or agricultural practices
Preparation of Soil
The preparation of soil is the first step before growing a crop.
It involves turning and loosening the soil as a result of which the nutrient-rich soil comes to the top. It also helps the roots to penetrate deep into the soil.
The loosened soil helps in the growth of earthworms and microbes present in the soil.
The process of loosening and turning of the soil is called tilling or ploughing.
This is done by using a plough which are made of wood or iron.
The ploughed field may have big clumps of soil called crumbs.
In order to get better yield, it is necessary to break these soil clumps.
This is done with the help of various tools such as plough, hoe and cultivator.
Fig: The Plough
Sowing
Sowing of seeds at appropriate depths and distances gives good yield.
Good variety of seeds are sown after selection of healthy seeds.
Sowing is done by seed drills uniformly at equal distance and depth.
Adding Manure and Fertilisers
The substances which are added to the soil in the form of nutrients for the healthy growth of plants are called manure and fertilisers.
Manure is an organic substance obtained from the decomposition of plant or animal wastes.
Fertilisers are chemicals which are rich in a particular nutrient.
Natural, Organic substance obtained by the decomposition of cattle dung
and plant residues.
Prepared in factories
Prepared in fields
Does not provide humus to the soil
Provides humus to the soil
Rich in plant nutrients like nitrogen, phosphorus and potassium.
Less rich in plant nutrients
Advantages of Manure over fertilisers
it enhances the water holding capacity of the soil.
it makes the soil porous due to which exchange of gases becomes easy.
it increases the number of friendly microbes.
it improves the texture of the soil.
Irrigation
The supply of water to crops at regular intervals is called irrigation.
Sources of irrigation
wells
tubewells
ponds
lakes
rivers
dams
Methods of Irrigation
Traditional Methods of Irrigation
Modern Methods of Irrigation
Traditional Methods of Irrigation
Cattle or human labour is used in these methods.
The various traditional ways are:
(i) moat (pulley-system)
(ii)Chain Pump
(iii) dhekli,
(iv) rahat (Lever system)
Modern Methods of Irrigation
(i) Sprinkler System
(ii) Drip system
Sprinkler Irrigation
Sprinkler Irrigation is a method of irrigation where water is distributed through a system of perpendicular pipes usually by pumping.
The perpendicular pipes, having rotating nozzles on top, are joined to the main pipeline at regular intervals.
When water is allowed to flow through the main pipe under pressure with the help of a pump, it escapes from the rotating nozzles and gets sprinkled on the crop as if it is raining.
Advantages and Disadvantages of Sprinkler Irrigation:
Eliminates water conveyance channels, thereby reducing water loss through these channels.
Suitable in all types of soil except heavy clay.
Saves up to 30% – 50 % water.
Suitable for irrigation where the plant population per unit area is very high.
Helps to increase yield.
Reduces soil compaction.
Suitable for undulating land.
Soluble fertilizers and chemicals use are possible.
Reduces labor cost.
Disadvantages:
It requires a high initial investment.
Power requirement is usually high since sprinklers operate with more than 0.5 kg/cm2 water pressure.
Fine textured soils that have low infiltration rate cannot be irrigated efficiently in a windy area.
Loss of water due to evaporation from the area during irrigation.
Wind distorts sprinkler pattern and causes uneven distribution of water.
Drip Irrigation
In this system, the water falls drop by drop directly near the roots. So it is called drip system. It is the best technique for watering fruit plants, gardens and trees
Advantages:
Maximum use of available water.
No water being available to weeds so weed control is efficient.
Maximum crop yield.
High efficiency in the use of fertilizers.
Soil erosion is eliminated.
Improved infiltration in the soil of low intake
No runoff of fertilizers into groundwater.
Fewer evaporation losses of water as compared to surface irrigation.
Improves seed germination.
Disadvantages:
Sensitivity to clogging.
Moisture distribution problem.
Salinity hazards.
High cost compared to furrow.
High skill is required for design, install, and operation.
Protection from weeds
Weeds are the undesirable plants that grow naturally along with the crop.
The removal of weeds is called weeding.
Methods of weeding
Tilling -helps in uprooting and killing of weeds
Manual removal – physical removal of weeds by uprooting or cutting them close to the ground using a khurpi and seed drill.
Weedicides- chemicals sprayed in the fields to kill the weeds.
Harvesting
The cutting of crop after it is mature is called harvesting.
In India harvesting is either done manually by sickle or by a machine called harvester.