Improvement in Food Resources

India's population keeps growing every year, so the amount of food grown must also keep growing — simply having more mouths to feed means the country cannot depend on last year's harvest levels. At the same time, the limited farmland available cannot be increased easily, so the only real option is to grow more food from the same or less land, in a way that does not damage the soil, water and environment for future harvests.

Scientists and farmers work on this problem from three connected directions, all covered in this chapter:

• Crop variety improvement — breeding better seeds that give higher yield, resist disease and survive bad weather.
• Crop production management — using nutrients (manures/fertilizers), irrigation and smart cropping patterns to help every plant grow to its full potential.
• Crop protection management — protecting the standing crop and the stored grain from weeds, pests, diseases and storage losses.

Alongside crops, animal husbandry (the scientific management of livestock, poultry, fish and bees) supplies milk, eggs, meat, fish and honey, which together with cereals, pulses and vegetables make up a balanced food basket.

Worked example: Suppose the average wheat yield in a region was 1 tonne per hectare before high-yielding varieties (HYVs), assured irrigation and balanced fertilizer use were introduced, and rose to 3 tonnes per hectare afterward.

Percentage increase in yield = (New Yield − Old Yield) ÷ Old Yield × 100 = (3 − 1) ÷ 1 × 100 = 200%. This shows how combining better varieties with better management can multiply food production from the same land.

Crop variety improvement means developing new, better versions of a crop through breeding, so that farmers get more and better-quality produce from the same field. Plant breeders select and combine specific, desirable characteristics — this is different from simply growing an existing variety more carefully.

The main traits that breeders aim to improve are:

• Higher yield — more grain, fruit or fibre per hectare.
• Improved quality — for example, more protein in pulses, better oil content in oilseeds, or better baking quality in wheat.
• Biotic resistance — resistance to diseases caused by bacteria, fungi and viruses, and to insect pests.
• Abiotic resistance — tolerance to drought, waterlogging, salinity, heat, cold and frost.
• Change in maturity duration — a shorter duration lets a farmer grow more crop cycles in a year (multiple cropping) and saves water and input costs.
• Wider adaptability — the ability of one variety to grow well across different climates and soils, so it can be recommended in many regions.
• Desirable agronomic characteristics — for example, dwarfness in cereals so the plant does not fall over (lodge) and can absorb more nitrogen fertilizer to produce more grain instead of more straw.

These improvements are achieved mainly by:

1. Introduction — bringing in and directly cultivating a variety that already performs well elsewhere.
2. Selection — repeatedly choosing and breeding only the best-performing plants from an existing mixed population.
3. Hybridization — crossing two genetically different parent plants (between varieties, between species of the same genus, or even between genera) so the offspring combines the good traits of both parents.
4. Mutation breeding — using radiation or chemicals to create random genetic changes, then selecting the rare useful mutants.
5. Genetic engineering — inserting one specific useful gene from an unrelated organism directly into the crop's genome, producing genetically modified (GM) crops such as Bt cotton, which carries a gene from a bacterium that makes the plant resistant to certain insect pests.

Worked example: Suppose Parent 1 is a wheat variety with very high yield but is easily damaged by rust disease, and Parent 2 is a low-yielding variety that is naturally rust-resistant. Hybridizing them (P₁ × P₂) can produce an F₁ offspring variety that combines both desirable traits — high yield and rust resistance — in a single new variety.

A crop plant needs sixteen essential nutrients to grow. Air and water supply carbon, hydrogen and oxygen, while the soil must supply the remaining thirteen. Of these, six nutrients — nitrogen, phosphorus, potassium, calcium, magnesium and sulphur (N, P, K, Ca, Mg, S) — are needed in comparatively large amounts and are called macronutrients; the other seven — iron, manganese, zinc, copper, boron, molybdenum and chlorine — are needed only in tiny (trace) amounts and are called micronutrients. If a plant does not get a nutrient in the right amount, it shows deficiency symptoms and gives a poor yield.

Farmers supply these missing nutrients in two ways:

• Manures — organic matter produced by decomposing plant or animal waste (farmyard manure, compost, vermicompost) or by ploughing a green crop like sunn hemp into the soil (green manuring). Manures add only a small quantity of nutrients but greatly improve soil structure, add humus, increase water-holding capacity, and are eco-friendly and cheap to prepare locally.
• Fertilizers — commercially manufactured, nutrient-rich inorganic salts such as urea, super phosphate and muriate of potash. They act quickly and give a big boost to plant growth and yield, but excessive or imbalanced use over many years damages soil fertility, kills useful soil microorganisms, and pollutes water bodies when it washes off the field.

Water is equally essential, so different sources and methods of irrigation are used depending on availability: wells, canals, river-lift systems, tanks and rainwater harvesting are common sources. Traditional methods (moat/pulley systems, chain pumps, cattle-driven rahat) are cheap but use a lot of water and labour. Modern methods such as the sprinkler system (good for uneven or sandy land) and drip/trickle irrigation (delivering water drop by drop straight to the roots) use water far more efficiently and are especially valuable where water is scarce.

How crops are arranged in the field also affects output. In mixed cropping, two or more crops are sown together (often with mixed seeds) so that if one crop fails due to bad weather, the other still gives some yield. In intercropping, two or more crops are grown together but in a fixed pattern of rows (for example, two rows of soybean alternating with four rows of maize), which lets each crop use nutrients, sunlight and space efficiently without competing directly. In crop rotation, different crops are grown in planned succession on the same field over seasons — commonly a nitrogen-demanding cereal followed by a legume, whose root nodules fix atmospheric nitrogen and restore soil fertility naturally.

Worked example: Urea contains about 46% nitrogen by weight. If a wheat field needs 92 kg of nitrogen per hectare, the quantity of urea required is: Quantity of urea = Required nitrogen ÷ Fraction of N in urea = 92 kg ÷ 0.46 = 200 kg of urea per hectare.

Even a well-grown crop can lose much of its potential yield to unwanted competitors, disease and poor storage. Crop protection management covers weeds, pests and diseases in the standing crop, and losses of the harvested grain in storage.

Weeds are unwanted plants (such as Xanthium and Parthenium) that grow along with the crop and compete with it for nutrients, water, light and space, directly reducing yield. Weeds are controlled by preventive steps (using clean, weed-free seed and proper crop rotation), mechanical removal (hand weeding or tilling), and chemical weedicides (such as 2,4-D) sprayed before the weeds can produce seeds.

Pests and diseases damage crops by cutting roots, stems or leaves, sucking cell sap, boring into stems or fruits, or by infecting the plant with disease-causing bacteria, fungi and viruses that spread through soil, water, air, insects or infected seed. Control strategies include:

• Preventive/cultural methods — growing resistant varieties, sowing at the right time, rotating crops, and summer ploughing, which exposes buried pest larvae and pupae to the hot sun and to predator birds, killing many before the next sowing.
• Chemical control — pesticides, insecticides and fungicides act quickly but, if overused, can be toxic to humans and livestock, kill beneficial insects, cause resistance to develop in the pest, and leave harmful residue in food and the environment.
• Integrated Pest Management (IPM) — a combination of cultural, mechanical and biological methods (such as encouraging natural predators of the pest), using chemical pesticides only as a last resort and in minimum quantity. IPM is preferred because it is more economical, sustainable and far less damaging to the environment than routine chemical spraying.

Even after a good harvest, grain can be lost during storage due to biotic factors (insects, rodents, fungi, mites and bacteria) and abiotic factors (unsuitable moisture and temperature in the storage place). These cause quantitative loss (loss in weight), qualitative loss (poor taste, discoloration, lower nutrient value) and loss of seed germination capacity. Losses are minimised by properly drying the produce (first in the sun, then in the shade) before storage, fumigating the storage area with appropriate chemicals, and using clean, dry, pest-proof bins or silos.

Worked example: A godown stores 5000 quintals of wheat. Due to pest and moisture damage during storage, 400 quintals are lost. Percentage loss = (Quantity lost ÷ Quantity stored) × 100 = (400 ÷ 5000) × 100 = 8%. This means 92% of the stored wheat (4600 quintals) remains fit for use.

Animal husbandry is the scientific management and care of livestock — proper feeding, breeding, housing and disease control — to get more milk, eggs, meat, wool or fish from the same number of animals.

Cattle farming serves two purposes: milch animals (cows and buffaloes) are bred for milk, and draught animals are used for labour such as ploughing, irrigation and cart-pulling. Indigenous Indian breeds (such as Red Sindhi and Sahiwal) are naturally resistant to local diseases and tolerate the Indian climate well, while exotic/foreign breeds (such as Jersey) give a much longer lactation period. Cross-breeding the two combines disease resistance with high milk yield. Good cattle management needs a clean, well-ventilated shelter with a sloped floor for drainage, a balanced diet of roughage (dry and green fodder, rich in fibre) plus concentrates (protein and nutrient-rich feed), and regular vaccination against common cattle diseases.

Poultry farming rears domestic fowl for either eggs (layers) or meat (broilers), and cross-breeding Indian breeds (such as Aseel) with foreign breeds (such as Leghorn) has produced varieties with more and better chicks and lower maintenance needs. Broilers need a protein- and fat-rich diet, fast growth, and carefully controlled light, temperature and ventilation, while layers need more space, a controlled lighting schedule, and calcium-rich feed to form strong eggshells. Hygienic housing, clean feed and water, and routine vaccination keep flocks disease-free.

Fish production is obtained either by capture fishing — catching fish directly from natural marine or inland water bodies without any rearing — or by culture fisheries (aquaculture), where fish are farmed under controlled conditions for a much higher and more reliable yield. In composite fish culture, five or six fish species that feed in different zones of the same pond (surface feeders like catla, middle-zone feeders like rohu, and bottom feeders like mrigal and common carp) are stocked together, so they do not compete for the same food or space, and the total fish yield from the pond rises sharply.

Apiculture (bee-keeping) is the rearing of honey bees, most commonly the Indian bee Apis cerana indica, for honey and beeswax. It requires knowledge of bee behaviour, a suitable apiary location, catching and hiving swarms, and seasonal hive management. The quantity and quality of honey depend heavily on pasturage — the flowers available nearby for bees to collect nectar and pollen from — so bee-keeping is usually combined with growing crops like mustard or sunflower, which also benefit from better pollination by the bees.

Worked example: A layer poultry farm houses 100 hens, which together lay 85 eggs in a day. Laying percentage = (Number of eggs laid ÷ Number of hens) × 100 = (85 ÷ 100) × 100 = 85%, which indicates a well-managed, productive flock (a good layer flock typically maintains a laying percentage above 80%).