Food is essential for the survival of all living organisms. Plants are the primary producers that prepare food through photosynthesis, and animals depend on them directly or indirectly. With a growing human population, the demand for food is increasing rapidly, and it is a major challenge to produce enough food while keeping it nutritious and affordable.
The food we eat is broadly of two types - cereals, pulses, fruits and vegetables from crop plants, and milk, eggs, meat and fish from animals. Improvement in food resources means increasing the quantity and quality of food produced, both from crops and from animals.
In this chapter we study the different approaches used to improve crop yields - including crop variety improvement, crop production management and crop protection - as well as the improvement of animal husbandry, including cattle, poultry, fish and beekeeping.
Food provides us with carbohydrates, proteins, fats, vitamins and minerals. The main sources of food are:
Plants: - Cereals like wheat, rice and maize - these provide carbohydrates. - Pulses like gram, pea and lentil - these provide proteins. - Oilseeds like mustard, groundnut and sunflower - these provide fats. - Fruits and vegetables - these provide vitamins, minerals and roughage.
Animals: - Milk from cattle and buffalo. - Eggs and meat from poultry and animals. - Fish from marine and freshwater fisheries.
India has been successful in increasing the production of food grains since the Green Revolution, and in increasing milk production through the White Revolution.
Crop yields can be improved through three main approaches:
The aims of crop variety improvement are: 1. Higher yield: To produce more food per unit area. 2. Better quality: For example, better baking quality in wheat and higher protein content in pulses. 3. Biotic and abiotic resistance: To make crops resistant to diseases, insects, drought, salinity and heat. 4. Change in maturity duration: To shorten the growing time so that more crops can be grown in a year, or to lengthen it for storage purposes. 5. Wider adaptability: To grow crops in different climates and soil conditions. 6. Desirable agronomic characteristics: Such as dwarfness in cereals, which allows more plants to be grown per unit area.
New varieties are developed by hybridisation, which is the crossing of two genetically different plants. Hybridisation can be intervarietal (between two varieties of a plant), interspecific (between two species), or intergeneric (between two genera). The process of introducing a gene with desirable traits into a crop is called genetic engineering.
Nutrient management: Plants need nutrients for growth. The main nutrients required in large amounts are called macro-nutrients - nitrogen, phosphorus, potassium, calcium, magnesium and sulphur. Nutrients required in small amounts are called micro-nutrients - iron, manganese, zinc, copper, boron and molybdenum.
Manures and fertilisers supply these nutrients: - Manures: Organic substances made from decomposed plant and animal waste. Manure enriches the soil with nutrients and organic matter (humus), improves soil texture, increases the water-holding capacity and encourages the growth of useful micro-organisms. Manure is not as rich in nutrients as fertilisers. - Fertilisers: Commercially produced inorganic compounds containing specific nutrients such as nitrogen (urea), phosphorus (superphosphate) and potassium (potash). Fertilisers provide nutrients quickly but should be used in the right amount; excessive use can make the soil infertile.
Irrigation: Irrigation is the supply of water to crops at regular intervals. Sources of irrigation are wells, canals, rivers and ponds. The time and frequency of irrigation depends on the nature of the crop, the soil and the season. Water is very important for crops as it absorbs nutrients and is used in photosynthesis and transpiration.
Cropping patterns: Different cropping patterns are used to increase the yield per unit area: 1. Mixed cropping: Growing two or more crops together on the same land at the same time, so that if one fails the other may survive. 2. Intercropping: Growing two crops in definite rows on the same land at the same time to utilise space and nutrients better. 3. Crop rotation: Growing different crops in a sequence on the same land. Rotation of legumes with other crops replenishes nitrogen in the soil.
Storage of grains: Grains need proper storage in clean, dry and air-tight conditions. Improper storage leads to losses from insects, rodents, fungi and moisture. Modern storage facilities include silos and granaries.
Crops are damaged by weeds, insect pests and diseases.
Weeds: Weeds are unwanted plants that grow along with the crop and compete with it for nutrients, water, space and sunlight. Examples are Xanthium and Parthenium. Weeds are removed by manual methods (uprooting), mechanical methods (using trowels) and chemical methods (using weedicides like 2,4-D).
Insect pests: Insects and pests attack the crops, their stored grains and the produce. They are controlled by spraying insecticides and pesticides. Some insects are controlled biologically by natural predators.
Diseases: Plants are affected by bacterial, fungal and viral diseases, which reduce the yield. Fungal diseases include rust and smut in wheat, and red rot in sugarcane. Bacterial diseases include blight. Viral diseases include mosaic diseases. Plants can be protected by developing disease-resistant varieties and by using appropriate pesticides.
The excessive use of pesticides and weedicides is harmful, so they should be used in safe quantities.
Animal husbandry is the scientific management of animals for the production of milk, eggs, meat, wool and other products. It includes feeding, breeding, housing and the health care of animals.
Important practices of animal husbandry are: 1. Proper feeding with balanced rations. 2. Providing clean shelter. 3. Disease prevention through vaccination. 4. Selective breeding for desirable traits.
Cattle farming is the management of cows and buffaloes for milk and draught labour.
Milk-producing animals are called milch animals (dairy animals), such as cows like Sahiwal and Red Sindhi, and buffaloes like Murrah. Draught animals are used for farm work like tilling, irrigation and carting, such as cows and bullocks.
Cross-breeding is done between Indian breeds and exotic breeds to produce animals with both good milk yield and disease resistance. For example, cross-bred cows like Karan Swiss have high milk production.
The daily diet of cattle consists of: - Roughage: Green fodder, hay and silage, which provide fibre. - Concentrates: Grains and oil cakes, which provide energy and proteins.
Clean water, proper shelter and regular vaccination protect cattle from diseases.
Poultry farming is the raising of domesticated birds like chickens, ducks, geese and turkeys for eggs and meat. Improved poultry breeds are developed to produce more eggs (layers) and more meat (broilers).
Broiler chickens are raised for meat; they require more proteins, vitamins and energy in their feed and need careful temperature control. Layers are raised for eggs and need a diet with more calcium and vitamins.
Disease-free and low-cost housing, proper hygiene and vaccination keep the flock healthy. Poultry farming is affected by diseases like fowl cholera and viral infections, so cleanliness and vaccination are essential.
Fish is a rich source of protein and is obtained from two main sources - marine (sea) fisheries and inland (freshwater) fisheries.
Marine fisheries: Marine fish like pomphret, mackerel, tuna and sardines are caught by fishing trawlers and boats in the sea. Marine fishing is done using nets. In recent years, aquaculture (the culture of fish in the sea) has been developed.
Inland fisheries: Freshwater fish are obtained from rivers, lakes, canals and ponds. Common freshwater fish are catla, rohu and common carp. The culture of fish in enclosed water bodies is called aquaculture. Composite fish culture is a practice in which different species of fish with different food habits are cultured together in the same pond, so that all the food in the pond is utilised without competing.
Fish are a good source of proteins, vitamins and minerals, and fish farming provides a good income.
Apiculture is the practice of keeping bees for the production of honey and wax. Honey bees are kept in specially designed wooden boxes called hives.
The main products of apiculture are honey and beeswax. Honey is used as food and in medicines. Beeswax is used in the manufacture of cosmetics and polishes.
Beekeeping requires: 1. Knowledge of the behaviour and life cycle of bees. 2. Proper selection of bee species. 3. Management of bee colonies. 4. Protection from diseases and enemies of bees.
Beekeeping provides additional income to farmers, as the bees also help in the pollination of crops, which increases the yield of crops growing near the hives.
| Approach | Method | Purpose |
|---|---|---|
| Crop variety improvement | Hybridisation, genetic engineering | Higher yield, disease resistance |
| Crop production management | Nutrients, irrigation, cropping patterns | Increase yield per unit area |
| Crop protection management | Weeds, pests and disease control | Protect the crop |
| Animal Husbandry | Product | Practice |
|---|---|---|
| Cattle farming | Milk, draught labour | Cross-breeding, feeding, vaccination |
| Poultry farming | Eggs, meat | Improved breeds, hygiene |
| Fish production | Fish (protein) | Marine and inland fisheries, aquaculture |
| Beekeeping | Honey, wax | Hives, colony management |
| Type of Nutrient | Examples | Role |
|---|---|---|
| Macro-nutrients | N, P, K, Ca, Mg, S | Needed in large amounts |
| Micro-nutrients | Fe, Mn, Zn, Cu, B, Mo | Needed in small amounts |
In this chapter we learned that with a growing population, improving food resources is essential. Crop yields can be improved through variety improvement by hybridisation, through production management using manures, fertilisers, irrigation and proper cropping patterns, and through protection management against weeds, pests and diseases. Animal husbandry complements crop production, providing milk, eggs, meat, fish, honey and wax through cattle farming, poultry farming, fisheries and beekeeping. The Green Revolution increased grain production, and the White Revolution increased milk production. By applying scientific principles to farming and animal rearing, we can ensure food security for a growing nation while maintaining the health of our soils, water and environment.