Chapter 1 : Crop Production and Management
Crops Definition
Green plants can synthesise their food by the process of photosynthesis by using inorganic substances like carbon dioxide, water in the presence of sunlight.
Man and other animals cannot make food by photosynthesis, they need readymade organic food nutrients like carbohydrates, fats and proteins for their growth and development.
When the same kind of plants are grown in the fields on a large scale to obtain food like cereals, pulses, vegetables and fruits, is called a Crop.
For Example: A crop of wheat means that all the plants grown in the field are that of wheat.
A crop of rice means that all the plants grown in the field are that of rice.
Crops are grown in the soil in the fields by farmers.
Examples of cereal crops
Cereal crops : Wheat, paddy, maize, millet, barley.
Examples of pulses
Pulses: Gram, Peas, beans
Examples of Oil Seeds
Oil seeds: Mustard, groundnut, sunflower
Examples of Vegetables
Vegetables: Tomato, cabbage, spinach.
Examples of Fruits
Fruits: Banana, grapes, mango, orange, apple.
Types of Crops
Based on the seasons all the crops are categorised into two main groups:
- Kharif crops
- Rabi crops
Kharif Crops
The crops which are sown in the rainy season are called kharif crops.
The sowing for kharif crop starts in June-July at the beginning of south-west monsoon because these crops need substantial amount of water.
The kharif crops are harvested at the end of monsoon season during September or October.
For Example: Paddy, maize, millet, soyabean, groundnut, cotton.
Paddy is grown only in rainy season because it requires a lot of water.
If wheat is sown in the kharif season, it will not grow well. This is because wheat plants cannot tolerate too much water of the rainy season.
Rabi Crops
The crops grown in the winter season are called rabi crops.
The time period of rabi crops is generally from october-march.
The sowing for rabi crops beings at the beginning of winter and the crops are harvested by march or april.
For Example: wheat, gram, peas, mustard, linseed etc.
Agriculture
The growing of plants or crops in the field for obtaining food is called agriculture.
Agricultural Practices
The various tasks performed by a farmer to produce a good crop are called agricultural practices.
Agricultural Implements
The various agricultural practices require certain tools or implements which are called agricultural implements.
Soil
The upper layer of earth is called soil.The crop plants are grown in soil.
Soil provides minerals,water,air,humus and fixing to the plants.
The soil is prepared for sowing the seeds of the crop by
- Ploughing
- Levelling
- Manuring
Ploughing
The process of loosening and turning of soil is called ploughing.
Ploughing of fields is done by using an implement called plough. Plough are made up of wood or iron and they have an iron tip for easy penetration into the soil. The ploughs are pulled by tractor or a pair of bullocks.
The loosening of soil by ploughing is beneficial because
- The loose soil allows the plant roots to penetrate freely and deeply into the soil so that plants are held more firmly to the ground.
- The loose soil allows the roots of plants to breathe easily.
- The loose soil help in the growth of worms and microbes present in the soil who are friends of the farmer.
- It also uproots and buries weeds standing in the field.
- It brings the nutrient rich soil to the top so that the plant can use these nutrients.
Soil Erosion
The removal of top soil by wind and water is called soil erosion.
Levelling
The ploughed soil is levelled by pressing it with a wooden leveller so that the top soil is not blown away by wind or drained off by water.
The levelling of ploughed soil is beneficial because :
- The levelling of ploughed fields prevents the top fertile soil from being carried away by strong winds or washed away by rain water.
- The levelling of ploughed fields helps in the uniform distribution of water in the fields during irrigation.
- The levelling of ploughed fields helps in preventing the loss of moisture.
The levelling of ploughed soil in the field is done by using an implement called Leveller. It is a heavy wooden plank or an iron plank.
Manuring
Manure is added to the soil before ploughing.Addition of manures to soil before ploughing helps in the proper mixing of manures with the soil.
Manuring is done to in increase the fertility of the soil before seeds are sown in it.
Agricultural Practices
The various tasks performed by a farmer to produce a good crop are called agricultural practices.
Agricultural Implements
The various agricultural practices require certain tools or implements which are called agricultural implements.
Soil
The upper layer of earth is called soil.The crop plants are grown in soil.
Soil provides minerals,water,air,humus and fixing to the plants.
The soil is prepared for sowing the seeds of the crop by
- Ploughing
- Levelling
- Manuring
Ploughing
The process of loosening and turning of soil is called ploughing.
Ploughing of fields is done by using an implement called plough. Plough are made up of wood or iron and they have an iron tip for easy penetration into the soil. The ploughs are pulled by tractor or a pair of bullocks.
The loosening of soil by ploughing is beneficial because
- The loose soil allows the plant roots to penetrate freely and deeply into the soil so that plants are held more firmly to the ground.
- The loose soil allows the roots of plants to breathe easily.
- The loose soil help in the growth of worms and microbes present in the soil who are friends of the farmer.
- It also uproots and buries weeds standing in the field.
- It brings the nutrient rich soil to the top so that the plant can use these nutrients.
Soil Erosion
The removal of top soil by wind and water is called soil erosion.
Levelling
The ploughed soil is levelled by pressing it with a wooden leveller so that the top soil is not blown away by wind or drained off by water.
The levelling of ploughed soil is beneficial because :
- The levelling of ploughed fields prevents the top fertile soil from being carried away by strong winds or washed away by rain water.
- The levelling of ploughed fields helps in the uniform distribution of water in the fields during irrigation.
- The levelling of ploughed fields helps in preventing the loss of moisture.
The levelling of ploughed soil in the field is done by using an implement called Leveller. It is a heavy wooden plank or an iron plank.
Manuring
Manure is added to the soil before ploughing.Addition of manures to soil before ploughing helps in the proper mixing of manures with the soil.
Manuring is done to in increase the fertility of the soil before seeds are sown in it.
Definition of Sowing
The process of scattering seeds in the ground soil for growing the crop plants is called sowing. Before sowing good quality seeds are selected.
Methods of sowing seeds
There are two methods of sowing the seeds in the soil.These are:
1) Sowing by hand
2) Sowing with a seed drill
Sowing by hand
The seeds are taken in hand and gradually scattered in the entire ploughed field.
Disadvantages
1) There is no proper spacing or proper depth at which seed are sown.
2) The seeds scattered on the surface of the soil for sowing can be picked up and eaten by the birds.
Sowing with a seed drill
A seed drill is a long iron tube having a funnel at the top.The seed drill is tied to back of the plough and seeds are put into the funnel of the seed drill.As the plough makes furrows in the soil,the seed from seed drill are gradually released and sown into the soil.
Advantages of Sowing with a dril
1) The seeds are sown at the correct depth and correct interval.
2) The seeds get covered by soil. Due to this these seeds cannot be picked up and eaten by the birds.
3) The seeds sown with a seed drill are in regular rows.
4) It saves time and labour.
Precautions for sowing seeds
1) The seeds should be sown at right depth in the soil.
2) The seeds should be sown at right interval or spacing.
3) The seeds should not be sown in a dry soil.
4) The seeds should not be sown in a highly wet soil.
Manures
Repeated growing of crops in the same field removes a lot of precious minerals, elements,organic matter and other material from the soil.
Due to this soil become infertile after some time,and the crop yield decreases.
The deficiency of plant nutrients and organic matter in the soil is made by adding manures and fertilisers to the soil.
A manure is a natural substance obtained by the decomposition of animal waste, human waste, plant residue by the action of micro-organism,which supplies essential elements and humus to the soil and makes it more fertile.
Advantages of Manures
1)It enhances the water holding capacity of the soil.
2)It makes the soil porous due to which the exchange of gases become easy.
3)It increases the number of useful microbes in the soil.
4)It improves the texture of the soil.
Disadvantages of Manures
1)They are very bulky and voluminous due to which it is inconvenient to store and transport.
2)They are not nutrient specific.
Fertilisers
A chemical fertiliser is a salt or an organic compound containing the necessary plant nutrient like nitrogen,phosphorus or potassium to make the soil more fertile.
For Ex:Urea,ammonium sulphate,superphosphate,potash,NPK.
Advantages of using Fertilisers
1)They provide quick replenishment of plant nutrients in the soil and restores soil fertility.
2)They are easily absorbed by the plants.
3)They are easy to transport,store and handle because they come in bags.
4)The use of fertilisers has helped the farmers to get better yields of crops such as wheat,maize,rice.
Harmful effects of fertilisers
1)The excessive use of fertilisers changes the chemical nature of soil and makes the soil less fertile.
2)The excessive use of fertilisers causes water pollution in ponds,lakes and rivers.
Difference between Manures and Fertilisers
|
Manures |
Fertilisers |
|
It is a natural substance obtained by decomposition. |
A chemical fertiliser is a salt or an organic compound |
|
A manure is not very rich in essential plant nutrients. |
Fertilisers are rich in plant nutrient like nitrogen, phosphorus or potassium. |
|
A manure provide a lot of humus to the soil. |
Fertiliser does not provide any humus to the soil. |
|
A manure is absorbed slowly by the plant . |
They are easily absorbed by the plants. |
|
They can be prepared in the fields. |
They are prepared in factories. |
Crop Rotation
The pulses,peas,beans,groundnut,gram etc are leguminous crops.
The root nodules of leguminous plants have nitrogen fixing bacteria(called Rhizobium)which can directly convert atmospheric nitrogen into nitrogen compounds.These nitrogen compounds go into the soil and improves the fertility.
The practice in which different types of crops are grown alternately in the same field or soil is called crop rotation.
In crop rotation cereal crops like wheat, maize,paddy, millet are grown alternately with leguminous crops like pulses,peas,beans,groundnut,clover in the same field.
Advantages of Crop Rotation
1)It improves the fertility of the soil by replenishing it with nitrogen and hence increases production of food grains.
2)It saves lots of nitrogenous fertilisers.
Irrigation
The process of supplying water to crop plant in the fields is called irrigation.
Why Irrigation is necessary
1)Irrigation before ploughing the fields makes the soil soft due to which the ploughing of fields become easier.
2)Irrigation is necessary to maintain the moisture for the germination of seeds.
3)Irrigation is necessary for absorption of nutrient element by the plant from the soil.
4)Irrigation is necessary to protect the crop plant from hot air currents as well as frost.
Factors affecting irrigation
1)Nature of crop:Each crop need specific amount of water during the various stages of its growth and ripening.Some crops need more water whereas others require less water.
For Ex:Paddy crop requires continuous irrigation whereas wheat,gram,cotton do not require so much water.
2)Nature of the soil:The crops grown in a sandy soil need irrigation more frequently whereas the frequency of irrigation for the crops grown in a clayey soil is less.
3)Season:The frequency of irrigation of the crops is higher in summer season as compared to that in winter season.
Sources of Irrigation
The various sources of irrigation are rivers, canals, wells, tubewell, dams, ponds, lakes, rain.
Traditional method of Irrigation
The various traditional method of irrigation are
(1) Moat (pulley system)
(2) Chain pump
(3) Dhekli
(4) Rahat (lever system)
Traditional method of irrigation are cheaper but less efficient. Pumps are commonly used for lifting water. These pumps run by electricity, diesel, biogas or solar energy.
When a pump is used to draw out water from a narrow well, it is called tube-well. They are used increasingly for lifting underground water to be used for irrigation in agriculture.
Modern methods of Irrigation
The two main modern methods of irrigation are:
(1) Sprinkler system
A main pipeline is laid in the field. Perpendicular pipes having rotating nozzles at the top are joined to the main pipelines at regular intervals. When water from a tube-well is allowed to flow through the main pipelines under pressure with the help of a pump, it escapes from the rotating nozzles. This water gets sprinkled on the crop plants as if it is raining.
Advantages of sprinkler system
(1) It is more useful for the uneven land where sufficient water is not available.
(2) It is very useful for sandy soil.
(2) Drip System
There is network of narrow pipes with small holes in the fields. When water flows through the narrow pipes, it fall drop by drop at the position of roots of the plants. This water is absorbed by the soil in the root zone of the plants and utilised by the plant. There is no wastage of irrigation of water.
Advantages of Drip System
(1) It provides water to plants drop by drop. So water is not wasted at all.
(2) It minimises the use of water in agriculture. It is useful in those regions where the availability of water is poor.
Weeding
The unwanted plants which grow along with a cultivated crop are called weed.
The type of weed vary from field to field,crop to crop,season to season.
For Ex:Wild oat,grass, Amaranthus, chenopodium etc.
The process of removing weeds from a crop field is called weeding.
Why Weeding is necessary
Weeding is necessary because
1)Weeds compete with crop plant for water,sunlight,nutrients,space and hence affect plant growth.
2)Some weeds are poisonous for human and animals whereas some weeds interfere in harvesting.
Methods of removal of weeds
1)Removal of weeds by pulling them out with hand.
2)Removal of weeds by using a trowel(khurpa)
3)Destroying the weeds by spraying weedicides:The poisonous chemicals which are used to kill weeds in the fields are called as weedicides.
For Example:2,4-D, MCPA, Butachlor etc.
The weedicides kill the weeds but do not damage the main crop.
Harvesting
It normally takes about three or four months for a crop to mature.
The cutting and gathering of the matured food crop is called harvesting.
Manual Harvesting
The crops like wheat or rice are cut close to the ground by hand using a cutting tool called sickle.This is called manual harvesting.
In large fields,wheat and paddy crops are cut by a motorised machine called harvester.
The process of beating out the grains from the harvested crop plant is called threshing.
Threshing is done to take out the grain from its outer covering called chaff.
In the traditional method of threshing,the harvested crop is spread on the ground in a small area and various cattle are made to walk over it again and again in a circle.The cattle’s feet crush the harvested crop plant due to which the chaff breaks up and the grain comes out.
Thresher
A motorised machine called thresher is also used for the threshing process.
Winnowing
The process of separating grain from chaff and hay with the help of wind is called winnowing.
When the grains mixed with chaff and hay is made to fall from a height in blowing wind,the grains,being heavy falls straight to the ground whereas the chaff and hay being much lighter are carried some distance away by the wind.
Storage of Food Grains
The food grains obtained by harvesting the crops are dried in the sunshine before storing to reduce their moisture content.It is necessary to prevent them from spoilage.
The higher moisture content in food grains promotes the growth of fungus and moulds on the stored grains which damages them.
The farmers store the dried food grains at home in metal bins (metal drums) and jute bags(gunny bags).Dried neem leaves are used for storing food grains at home.
The government agency like Food Corporation of India(FCI) buy grains from farmers on large scale and store it in big godowns.
What are the ways to store food grains on a large scale
The large scale storage of food grains is done in two ways:
1)In gunny bags
2)In grain sillos
Pesticide solution are sprayed on the stacked gunny bags in the godown from time to time to protect them pests during storage.
