Agribusiness Management · Foundations · also Agriculture and Food Systems (MANAGE), Bridge course for non-agriculture graduates
The farm science an agribusiness manager must know: crops, soils, pests, horticulture, livestock, irrigation and post-harvest. Agribusiness master's entrance syllabi draw roughly a fifth to a quarter of their questions from this ground.
In the exams: agricultural master's entrance examinations, agribusiness, about 20–25% of the paper (heavy); agricultural master's entrance examinations, agricultural economics (present); agricultural development bank officer recruitment, agriculture and rural development (heavy); professional-knowledge papers in agricultural field officer recruitment in banking (heavy)
Agriculture and Food Systems is the bridge course that every agribusiness programme runs in its first term. Students arrive from commerce, engineering or the humanities and within a year must appraise a dairy loan, plan procurement for a rice mill or advise a food company on sourcing. That needs working knowledge of how crops grow, why soils run short of nitrogen, how long a cow carries a calf and why a tomato bruises and wheat does not: enough biology and engineering to question an agronomist or veterinarian, and enough arithmetic to check the answer.
The course follows the food system from end to end. It runs from agriculture's place in economies and trade, through farming systems, inputs and yield gaps, crops, soils, pests, horticulture, forestry, livestock and veterinary basics, water, machinery and energy, post-harvest handling and processing, food security, and finally sustainability and the research and extension institutions. Worked calculations sit where each concept is taught, because examiners and employers expect a manager to compute, not only recall.
In India, the ICAR AIEEA-PG paper for Agri-Business Management (Group 19) states that around a fifth to a quarter of its questions come from agriculture and allied sciences, and the Social Sciences group tests the same base in its first unit. Bank recruitment for agricultural officers (IBPS AFO, NABARD Grade A) leans heavily on crops, soils, livestock and irrigation. Agribusiness programmes from Wageningen to Los Baños to Nairobi teach the same content as a foundation module assessed through cases. Examples lean on South Asia, where the examination load is heaviest, with other regions noted where practice differs.
As national income rises, the share of agriculture in gross domestic product (GDP) falls. This is the structural transformation described by Kuznets and Chenery, and it follows from Engel's law: as households get richer they spend a smaller share of income on food, so demand for farm output grows more slowly than demand for manufactures and services. It is one or two per cent of GDP in rich countries but a fifth or more in many low-income ones. Employment share falls far more slowly, so output per farm worker stays low.
In India, agriculture and allied activities (crops, livestock, forestry and fisheries) have contributed roughly a sixth to a fifth of gross value added in recent Economic Surveys while employing close to half of the workforce in labour force surveys. Check the latest survey before quoting figures.
Kuznets, and later Johnston and Mellor, stated agriculture's importance as four contributions. The product contribution is food and raw materials for industry. The factor contribution is the release of labour and savings to other sectors. The market contribution is rural demand for industrial goods such as fertiliser, machinery, clothing and consumer goods. The foreign-exchange contribution is export earnings or import savings. Backward linkages run to input industries and forward linkages to processing, storage, transport and retail; most value in a modern food system is added off the farm.
A food system is the whole set of activities and actors that produce, aggregate, process, distribute, prepare and consume food, together with their outcomes for nutrition, income and the environment. Upstream sit seed, fertiliser, crop-protection, machinery, feed, veterinary and credit suppliers; on the farm, smallholders, estates and corporate farms; downstream, traders, cooperatives and producer organisations, warehouses, processors, exporters, retailers, food service and consumers.
Three features of food systems shape every business decision in this course. First, seasonality: most crops are harvested in a few weeks but consumed all year, which creates the need for storage, finance and price risk management. Second, perishability: fruits, vegetables, milk, meat and fish deteriorate in hours or days, so cold chains and rapid processing carry a premium. Third, biological and weather risk: output depends on rainfall, temperature, pests and disease, so yields and prices are volatile in ways that factory output is not.
The farmer's share of consumer spending is high for minimally processed staples and low for packaged foods.
Only part of world food production is traded across borders, and the share differs sharply by commodity. Wheat and soybeans are heavily traded; rice is a thin market, with only about a tenth of world production or less crossing borders in most years, which is one reason rice prices swing sharply when a large exporter restricts sales. The major wheat exporters are Russia, the European Union, Canada, the United States, Australia and Ukraine. Rice exports are led by India, followed by Thailand, Vietnam and Pakistan. Maize exports come mainly from the United States, Brazil, Argentina and Ukraine. Soybean exports are dominated by Brazil and the United States, and China is by far the largest importer. India is the world's largest producer of milk and of pulses, a major importer of edible oils and pulses, and one of the two largest producers of rice and wheat together with China.
Trade follows comparative advantage: land-abundant countries export grains and oilseeds; labour-abundant ones, fruits, vegetables, spices and aquaculture. Trade is also shaped by policy. The World Trade Organization Agreement on Agriculture (in force from 1995) disciplines three areas: market access (tariffs and tariff-rate quotas), domestic support (classified into amber, blue and green boxes) and export competition (export subsidies). Sanitary and phytosanitary rules, referenced to Codex, WOAH and the IPPC, often matter more to exporters than tariffs. The 2007-08 price spike showed how export restrictions amplify shortages in thin markets.
Crops are grown where temperature, rainfall, soil and day length allow. Agro-climatic and agro-ecological zoning groups land with similar conditions so that research, crop recommendations and credit norms can be targeted. Globally, the FAO and IIASA Global Agro-Ecological Zones (GAEZ) framework uses the length of growing period, the number of days in a year when both moisture and temperature permit crop growth, with soil and terrain data, to estimate attainable yields.
India uses three overlapping systems. The Planning Commission in the late 1980s divided the country into 15 agro-climatic regions for planning. The National Agricultural Research Project (NARP) of ICAR defined around 127 smaller agro-climatic zones to guide the work of regional research stations. The National Bureau of Soil Survey and Land Use Planning delineated 20 agro-ecological regions using physiography, soils, bioclimate and length of growing period.
Crop seasons follow climate. In South Asia the kharif season crops are sown with the onset of the south-west monsoon (June-July) and harvested in autumn; rabi crops are sown in October-November on stored soil moisture or irrigation and harvested in March-April; zaid crops are short summer crops between them. In temperate regions the equivalent distinction is between winter-sown and spring-sown crops, for example winter wheat and spring wheat. Day length matters too: rice and soybean are mostly short-day plants that flower as days shorten, while wheat is a long-day plant.
A farming system is the whole farm as managed by a household or firm: its crops, animals, trees, labour, capital and markets, and the interactions between them. Main types are shifting cultivation, in which forest is cleared, cropped for a few years and left to regenerate (called jhum in north-east India); pastoral systems, in which herders move livestock over rangeland, common in the Sahel, East Africa and Central Asia; mixed crop-livestock systems, in which crops feed animals and animals provide draught, manure and milk, the dominant smallholder system of South Asia and the East African highlands; irrigated rice-based systems of monsoon Asia; large mechanised grain farms of the Americas, Australia and the Black Sea; and plantations of tea, coffee, rubber, oil palm and sugar.
A cropping system is the pattern of crops on a piece of land over time. Sequential cropping grows crops one after another in the same year, such as the rice-wheat sequence that covers over ten million hectares of the Indo-Gangetic plains. Intercropping grows two or more crops at the same time in a definite row pattern, such as pigeonpea with sorghum; mixed cropping grows them together without a row pattern; relay cropping sows the second crop before the first is harvested. Cropping intensity measures how often land is cropped: gross cropped area divided by net sown area, times 100. A farm with 140 hectares net sown and 196 hectares gross cropped has a cropping intensity of 140 per cent.
Integrated farming systems link enterprises (rice, fish and ducks; crops, dairy and biogas) so that one's waste is another's input, spreading risk and income.
Purchased inputs are seed, fertiliser, water, crop protection, machinery services, energy and credit; owned inputs are land, family labour and management. Seed production in most countries follows a generation system: breeder seed produced by the breeder, then foundation seed, then certified seed sold to farmers. In India their tags are golden yellow, white and blue. Hybrid seed must be bought each season because the next generation segregates and loses vigour.
Seed rate in kilograms per hectare equals plants per square metre times 10,000 times 1000-seed weight in grams, divided by germination as a fraction, divided by one million. For wheat at 250 plants per square metre, a 1000-grain weight of 40 grams and 90 per cent germination, the seed rate is 250 times 10,000 times 40 divided by 0.9 divided by one million, or about 111 kilograms per hectare.
Yield is governed by the most limiting factor, an idea formalised as Liebig's law of the minimum, and by diminishing returns to any one input. Agronomists distinguish potential yield (a well-adapted variety with no limits from water, nutrients, pests or disease), water-limited potential yield for rainfed crops, attainable yield under good farm management, and actual farm yield. The yield gap is the difference between potential or attainable yield and actual yield, often expressed as a percentage. If attainable yield is 6 tonnes per hectare and the farm gets 3.9 tonnes, the gap is 2.1 tonnes, or 35 per cent of attainable yield. Gaps arise from biophysical limits, management (late sowing, poor seed, unbalanced fertiliser) and economics (prices, credit, risk).
Rice (Oryza sativa, the Asian species; Oryza glaberrima is the African species) belongs to the grass family Poaceae and is the staple of more than half of humanity. The classic Asian practice is to raise seedlings in a nursery, puddle the field by tilling it when flooded to reduce percolation, and transplant seedlings at three to four weeks. Alternatives that save water and labour include direct-seeded rice, alternate wetting and drying (letting the field dry until the water table falls a set depth below the surface before re-flooding), and the System of Rice Intensification, developed in Madagascar in the 1980s, which uses young single seedlings, wide spacing and intermittent irrigation. Flooded rice fields emit methane because organic matter decomposes without oxygen, so water management is also a climate issue. The semi-dwarf variety IR8, released by the International Rice Research Institute in 1966, launched the Green Revolution in rice.
Wheat is a cool-season cereal. Bread wheat (Triticum aestivum) is hexaploid; durum wheat (Triticum durum), used for pasta and semolina, is tetraploid. In South Asia wheat is a rabi crop sown in November. The most critical stage for irrigation is crown root initiation, about three weeks after sowing; missing it reduces tillering and yield more than missing any later irrigation. Semi-dwarf wheats carrying the Rht dwarfing genes, bred by Norman Borlaug's programme in Mexico, resist lodging under high fertiliser and were the basis of the wheat Green Revolution. Terminal heat during grain filling makes timely sowing a yield issue.
Pulses are the dry edible seeds of legumes (family Fabaceae). They fix atmospheric nitrogen through Rhizobium bacteria in root nodules, so they need little nitrogen fertiliser and leave some nitrogen for the following crop. Their protein is rich in lysine, the amino acid in which cereals are poor, which is why cereal-pulse diets such as rice with lentils are nutritionally complementary.
Chickpea (Cicer arietinum) is a cool-season rabi pulse, usually grown on residual soil moisture after the monsoon. There are two main types: desi, with small, angular, dark seeds and a thick seed coat, and kabuli, with larger, cream-coloured seeds that fetch a higher price. Nipping, the removal of the growing tips, encourages branching and more pods. India produces most of the world's chickpea and also imports it in short years. The pod borer Helicoverpa armigera and Fusarium wilt are its main biotic constraints.
Pigeonpea (Cajanus cajan), also called red gram or tur, is a deep-rooted, drought-tolerant kharif pulse. Traditional varieties are long-duration and are usually intercropped with sorghum, pearl millet, cotton, soybean or groundnut, because the pigeonpea grows slowly at first while the companion crop matures. ICRISAT developed the first commercial hybrids in a pulse crop using cytoplasmic male sterility. Its key problems are sterility mosaic disease, Fusarium wilt and pod borers.
Sugarcane (modern varieties are hybrids derived from Saccharum officinarum, the noble cane, crossed with Saccharum spontaneum and other species) is a perennial C4 grass that stores sucrose in its stalk. The Sugarcane Breeding Institute, Coimbatore, pioneered such hybrids. Cane is propagated vegetatively from setts, stem pieces with two or three buds. A planted crop takes about ten to eighteen months depending on region; after harvest the stubble regrows as a ratoon crop, which saves planting cost but usually yields less. Brazil is the largest producer and India the second. Sugar recovery, the kilograms of sugar per 100 kilograms of cane crushed, is the key figure for mills; in India it is commonly around ten to eleven per cent but varies by region, variety and season. A mill crushing 100 tonnes of cane at 10.5 per cent recovery makes 10.5 tonnes of sugar. By-products are bagasse (fibre, burnt for steam and power), molasses (for alcohol and ethanol) and press mud (used as manure).
Groundnut or peanut (Arachis hypogaea) is a legume oilseed from South America. Its distinctive habit is geocarpy: after the flower is fertilised, a stalk called the peg (gynophore) grows down into the soil and the pod develops underground. Because the developing pod absorbs calcium directly from the soil, gypsum applied at flowering and pegging improves pod filling and reduces empty pods. Kernels contain roughly 45 to 50 per cent oil. The most serious quality hazard is aflatoxin, a carcinogenic toxin produced by Aspergillus flavus when pods are damaged by drought, insects or poor drying; it is a frequent reason for export rejection.
Soil is the weathered surface layer of the earth in which plants root. Hans Jenny summarised its formation as a function of climate, organisms, relief (topography), parent material and time. Soil is described by texture, the proportions of sand, silt and clay particles (under the USDA scale, sand is 2 to 0.05 millimetres, silt 0.05 to 0.002 millimetres and clay below 0.002 millimetres); by structure, the way particles clump into aggregates; and by chemistry, especially pH, organic matter and cation exchange capacity (CEC), the soil's ability to hold positively charged nutrients such as calcium, magnesium and potassium.
The USDA Soil Taxonomy, used worldwide in research, has twelve soil orders. Vertisols are clay-rich soils that swell when wet and crack when dry; Oxisols are the deeply weathered soils of humid tropics; Mollisols are the dark, fertile grassland soils of the prairies and steppes. Indian soil groups include alluvial soils, the most extensive; black soils (regur), rich in swelling smectite clay and famous for cotton; red soils, low in nitrogen and phosphorus; and laterite soils, leached, acidic and rich in iron and aluminium oxides.
Problem soils need different remedies. Acid soils are corrected with lime. A saline soil has an electrical conductivity of the saturation extract above 4 decisiemens per metre, an exchangeable sodium percentage (ESP) below 15 and pH usually below 8.5; it is reclaimed by leaching salts out with good-quality water and drainage. A sodic (alkali) soil has ESP above 15 and pH above 8.5; it is reclaimed with gypsum, whose calcium replaces sodium on the clay, followed by leaching.
Seventeen elements are accepted as essential for higher plants: carbon, hydrogen and oxygen from air and water; the primary nutrients nitrogen (N), phosphorus (P) and potassium (K); the secondary nutrients calcium, magnesium and sulphur; and the micronutrients iron, manganese, zinc, copper, boron, molybdenum, chlorine and nickel. Arnon and Stout set the criteria of essentiality in 1939.
Mobile nutrients (N, P, K, magnesium) are moved from old leaves to new growth when supply is short, so their deficiency shows first on older, lower leaves. Immobile nutrients (calcium, boron, iron, and largely sulphur) cannot be moved, so deficiency shows first on young leaves and growing points.
Nitrogen deficiency gives pale green to yellow older leaves and stunted, thin plants; in cereals the yellowing starts at the leaf tip and runs down the midrib in a V shape. Phosphorus deficiency gives stunted plants with dark green leaves that turn purplish or reddish, especially on older leaves, poor root growth and delayed maturity. Potassium deficiency gives yellowing then browning and scorching along the margins and tips of older leaves, weak stems that lodge and poorly filled grain. Zinc deficiency in rice causes khaira disease, with rusty brown spots on older leaves and stunting, common on alkaline and continuously flooded soils. Iron deficiency causes yellowing between the veins of young leaves, typical of calcareous soils and aerobic rice. Calcium deficiency causes blossom-end rot in tomato. Confirm symptoms by soil or tissue tests.
Fertiliser content is stated as a grade: the percentages of N, of phosphorus as P2O5 and of potassium as K2O. Common grades are urea 46 per cent N; diammonium phosphate (DAP) 18 per cent N and 46 per cent P2O5; muriate of potash (potassium chloride) 60 per cent K2O; single superphosphate 16 per cent P2O5 with calcium and sulphur; ammonium sulphate about 21 per cent N with sulphur. To convert oxide to element, multiply P2O5 by 0.436 to get P and K2O by 0.83 to get K.
The basic calculation is: product needed equals nutrient needed divided by the nutrient fraction. To supply 120 kilograms of N per hectare from urea needs 120 divided by 0.46, about 261 kilograms of urea. The common slip is to multiply instead (120 times 0.46 = 55), which gives far too little. When a product carries two nutrients, account for both. To supply 60 kilograms of P2O5 from DAP needs 60 divided by 0.46, about 130 kilograms of DAP, which also supplies 130 times 0.18, about 23.5 kilograms of N. If the target is 100 kilograms of N, the remaining 76.5 kilograms comes from 76.5 divided by 0.46, about 166 kilograms of urea. Sixty kilograms of K2O from muriate of potash needs 100 kilograms of the product.
In India a 4:2:1 N:P2O5:K2O ratio is a common benchmark, while actual use has been nitrogen-heavy, partly because urea is the most subsidised fertiliser. The 4R nutrient stewardship framework asks for the right source, rate, time and place. Integrated nutrient management combines fertiliser with manure, compost, residues, green manure and biofertilisers such as Rhizobium, Azotobacter, Azospirillum, phosphate-solubilising bacteria and Azolla. Partial factor productivity is grain yield per kilogram of nutrient applied; agronomic efficiency is extra grain over the unfertilised plot per kilogram applied.
A pest is any organism that reduces crop yield or quality. Integrated pest management (IPM) combines cultural practices (resistant varieties, crop rotation, timely sowing, field sanitation), mechanical and physical measures (traps, barriers, hand-picking), biological control (natural enemies such as the egg parasitoid Trichogramma, the antagonistic fungus Trichoderma, Bacillus thuringiensis and nuclear polyhedrosis viruses) and chemical control used only when needed.
The key decision rule is the economic threshold level (ETL), the pest density at which control action should be taken to prevent the population from reaching the economic injury level (EIL), the density at which the value of damage equals the cost of control. The ETL is set below the EIL to allow time for the control to act. Pesticides must follow the label, including the pre-harvest interval; maximum residue limits set by Codex and national regulators differ between importers, and violations cause export rejections. Overuse causes resistance and resurgence, as with the rice brown planthopper.
Transboundary pests show why plant protection is an international matter. The FAO monitors the desert locust (Schistocerca gregaria). The fall armyworm (Spodoptera frugiperda), native to the Americas, spread to Africa in 2016 and to India in 2018, attacking maize above all. Wheat stem rust race Ug99, first identified in Uganda in 1999, overcame many resistance genes. History records the potato late blight that caused the Irish famine of the 1840s.
Rice. Blast, caused by the fungus Magnaporthe oryzae (asexual stage Pyricularia oryzae), produces spindle-shaped leaf lesions and neck rot that breaks the panicle. Bacterial leaf blight (Xanthomonas oryzae pv. oryzae) yellows leaf margins. The brown planthopper (Nilaparvata lugens) sucks sap at the base of the plant and causes circular patches of dried plants called hopperburn. The yellow stem borer (Scirpophaga incertulas) causes dead hearts at the vegetative stage and white, empty panicles (white ears) at heading.
Wheat. The three rusts are caused by Puccinia species: stem or black rust (P. graminis f. sp. tritici), leaf or brown rust (P. triticina) and stripe or yellow rust (P. striiformis). Loose smut (Ustilago tritici) is internally seed-borne, so it is controlled by seed treatment with systemic fungicide or by hot-water or solar treatment of seed. Karnal bunt (Tilletia indica) turns parts of grains into fishy-smelling black spores and is a trade quarantine concern.
Pulses. Gram pod borer (Helicoverpa armigera) is the main insect pest of chickpea and pigeonpea and also attacks cotton and tomato. Fusarium wilt affects both crops. Sterility mosaic of pigeonpea is transmitted by an eriophyid mite and makes plants bushy and flowerless.
Sugarcane. Red rot (Colletotrichum falcatum) reddens internal tissue with white cross-bands; it is called the cancer of sugarcane. Grassy shoot is a phytoplasma disease.
Groundnut. Early and late leaf spots (tikka disease) are fungal; white grubs damage roots and pods.
Tomato. Late blight (Phytophthora infestans) and early blight (Alternaria solani) attack leaves and fruit; tomato leaf curl is a virus spread by the whitefly Bemisia tabaci; fruit borer (Helicoverpa) and the leaf miner Tuta absoluta damage fruit and leaves.
Mango. Hoppers suck sap from flower panicles; fruit flies (Bactrocera species) are a major quarantine pest, so export fruit often needs hot-water or vapour-heat treatment or irradiation; powdery mildew, anthracnose and malformation also matter.
Horticulture covers fruits (pomology), vegetables (olericulture), flowers and ornamentals (floriculture), landscape gardening, plantation crops (tea, coffee, rubber, coconut, arecanut, cocoa), spices, and medicinal and aromatic plants. It earns and employs more per hectare than field crops, but produce is perishable and prices swing sharply. China is the largest producer of fruits and vegetables and India the second. In India horticultural output by tonnage has exceeded foodgrain output since the early 2010s, and India is the largest producer, consumer and exporter of spices.
Most fruit trees are propagated vegetatively so that every tree is true to the parent variety. Methods include cuttings, layering (rooting a shoot while still attached to the parent), grafting (joining a scion of the desired variety onto a rootstock) and budding (inserting a single bud). Mango is propagated mainly by veneer, softwood or stone (epicotyl) grafting.
Tomato (Solanum lycopersicum, family Solanaceae, originally from the Andes) is grown in open fields and under protection. Determinate varieties stop growing at a terminal flower cluster and ripen together, suiting processing and machine harvest; indeterminate varieties keep growing and fruiting and are usually staked. Mango (Mangifera indica, family Anacardiaceae, native to the Indo-Burma region) is the main fruit of South Asia, and India is by far its largest producer. Many varieties show alternate or biennial bearing, a heavy crop one year and a light crop the next. Indian varieties are generally monoembryonic, while many South-East Asian types are polyembryonic and come true from seed.
Fruits are classed by how they ripen. Climacteric fruits show a burst of respiration and ethylene production at ripening and can be harvested mature but unripe and ripened later: mango, banana, tomato, papaya, apple, avocado and guava. Non-climacteric fruits do not ripen further after harvest and must be picked ripe: citrus, grape, strawberry, pineapple, cherry and pomegranate. Climacteric fruit can therefore travel far and be ripened near market with controlled ethylene. Calcium carbide, an older ripening agent, is prohibited for fruit ripening in India and many other countries because of contamination and safety risks.
Protected cultivation uses greenhouses, polyhouses, shade-net houses and low tunnels to control temperature, light, humidity and pests. It allows off-season production, higher yields and better quality for high-value vegetables and flowers, at much higher capital cost. Horticultural quality is measured through size, colour, firmness, total soluble solids (sugar content measured in degrees Brix with a refractometer) and freedom from defects and residues.
Forests cover about 31 per cent of the world's land, about 4 billion hectares, according to the FAO Global Forest Resources Assessment 2020. Net forest loss is concentrated in the tropics, and agricultural expansion is the main driver. Forests supply timber, fuelwood and non-timber products (bamboo, honey, gums, lac, medicinal plants), protect watersheds and store carbon. In India forest cover is about a fifth of the geographical area according to recent State of Forest Reports, against the National Forest Policy of 1988 goal of one-third under forest or tree cover. Joint Forest Management, from 1990, involves village communities in protecting and sharing benefits from state forests.
Agroforestry is the deliberate growing of trees on the same land as crops or livestock. Its main systems are agrisilviculture (trees with crops, such as poplar with wheat in north-west India), silvopastoral (trees with pasture and animals) and agrosilvopastoral (all three). Farm trees give fodder, fuel, timber and fruit, reduce erosion, and add off-season income. A well-known African example is Faidherbia albida, which sheds its leaves in the rainy season and so does not shade the crops beneath it while dropping nitrogen-rich litter. India adopted a National Agroforestry Policy in 2014. Social forestry, a term popularised by India's National Commission on Agriculture in 1976, means growing trees on public and community land for local needs. REDD+ and voluntary carbon credits are newer income sources.
Livestock supply food, fibre, draught, manure and saleable wealth. FAO puts livestock at around 40 per cent of the global value of agricultural output; in India it is the fastest-growing part of agriculture, roughly 30 per cent of agriculture-and-allied value added in recent Economic Surveys. India is the world's largest milk producer, a position built on Operation Flood, launched in 1970 by the National Dairy Development Board, which linked village dairy cooperatives on the Anand pattern to urban markets.
Cattle come in two broad groups: humped zebu cattle (Bos indicus), which tolerate heat and ticks, and humpless taurine cattle (Bos taurus) of temperate origin. Holstein-Friesian is the highest-yielding dairy breed; Jersey gives less milk with high fat. Indian dairy breeds include Sahiwal, Gir and Red Sindhi; Tharparkar is dual-purpose; Hallikar, Kangayam, Amritmahal and Nagori are draught breeds. Murrah is the leading buffalo breed, with Nili-Ravi, Mehsana, Jaffarabadi and Surti also important. Buffalo milk has more fat than cow milk. Crossbreds with taurine bulls yield more milk but need better feed and care.
Poultry is split between broilers, raised for meat and marketed in about six weeks, and layers, which start laying at around 18 to 20 weeks; the White Leghorn is the classic layer breed. Goats (Jamunapari, Beetal, Barbari, Black Bengal; Boer for meat, Saanen for milk) need little capital. Pigs and poultry are monogastric and convert concentrate feed efficiently; ruminants convert grass and crop residues that people cannot eat.
Ruminants (cattle, buffalo, sheep, goats) have a four-compartment stomach: rumen, reticulum, omasum and abomasum, the last being the true glandular stomach. Rumen microbes ferment cellulose into volatile fatty acids (mainly acetic, propionic and butyric) for energy and make microbial protein. So ruminants can use straw, and limited urea as non-protein nitrogen. Rumen fermentation also produces methane, which the animal belches out; enteric methane is the largest single source of greenhouse gas from livestock. Feeds are roughages (fodder, hay, silage, straw) or concentrates (grains, oilcakes, brans).
Feed conversion ratio (FCR) is kilograms of feed per kilogram of live weight gain or product. A broiler batch that eats 3.4 kilograms of feed per bird and reaches 2.0 kilograms live weight has an FCR of 1.7. Lower is better; feed is the largest cost in poultry and pigs.
The oestrous (heat) cycle of cows and buffaloes is about 21 days. Approximate gestation lengths are: cow about 280 to 285 days, buffalo about 310 days, sheep and goats about 150 days, sow about 114 days, mare about 340 days; chicken eggs hatch in 21 days. A standard lactation record is 305 days, followed by a dry period of about 60 days before the next calving, and the economic target for dairy cattle is a calving interval of about 12 to 13 months. Milk yield per day of calving interval is a useful index: a cow giving 3,000 litres in a lactation with a 400-day calving interval yields 7.5 litres per day of calving interval. Calves need colostrum, antibody-rich first milk, within hours of birth.
Diseases are grouped by cause. Viral diseases include foot-and-mouth disease (FMD), which affects cloven-hoofed animals with blisters in the mouth and on the feet, sharp drops in milk yield, and severe trade restrictions; lumpy skin disease, a capripox virus of cattle spread by biting insects; peste des petits ruminants (PPR) of sheep and goats; rabies; Newcastle disease and avian influenza of poultry; and African swine fever of pigs. Bacterial diseases include haemorrhagic septicaemia (Pasteurella multocida), an acute disease of cattle and especially buffaloes in the monsoon; black quarter (Clostridium chauvoei), affecting young, well-fed cattle with gas-filled swellings in heavy muscles; anthrax (Bacillus anthracis), sudden death with unclotted dark blood from body openings, carcass not to be opened; brucellosis, which causes abortion in late pregnancy and undulant fever in people; tuberculosis; and mastitis, udder inflammation and the costliest dairy disease, often subclinical and found only by somatic cell counts.
Vaccination, deworming, milking hygiene and quarantine of new animals prevent most losses. India's National Animal Disease Control Programme, begun in 2019, targets FMD and brucellosis through mass vaccination.
Rinderpest was declared eradicated worldwide in 2011, only the second disease after smallpox; PPR is now targeted for global eradication by 2030 under an FAO and World Organisation for Animal Health (WOAH, formerly OIE) strategy. About 60 per cent of known human infectious diseases and about three-quarters of emerging ones are zoonotic, which is the basis of the One Health approach linking human, animal and environmental health. Antibiotic misuse in animals feeds antimicrobial resistance; every veterinary drug has a withdrawal period during which milk, meat or eggs must not be sold — confirm doses and withdrawal periods against the product label and your national formulary.
Agriculture accounts for roughly 70 per cent of global freshwater withdrawals according to FAO AQUASTAT. Irrigated land is about a fifth of the world's cultivated area but produces around 40 per cent of its food. In India roughly half the net sown area is irrigated, mostly from groundwater, and water tables have fallen sharply in Punjab and Haryana.
Crop water need is estimated from evapotranspiration. The FAO-56 method computes a reference evapotranspiration (ETo) from weather data with the Penman-Monteith equation and multiplies it by a crop coefficient (Kc) that changes with crop stage: ETc = Kc times ETo. With ETo of 5 millimetres a day and a mid-season Kc of 1.15, the crop uses about 5.75 millimetres a day. Soil stores water between field capacity (the water held after free drainage, at a suction of about one-third bar) and the permanent wilting point (about 15 bar); the difference is the available water. Irrigation is scheduled by depletion of available water, by critical stages, or by the ratio of irrigation depth to cumulative pan evaporation.
Depth converts to volume simply: one millimetre over one hectare is 10 cubic metres, so one centimetre is 100 cubic metres or 100,000 litres. Applying 5 centimetres to 2 hectares needs 1,000 cubic metres; a pump delivering 25 litres per second takes 1,000,000 divided by 25, or 40,000 seconds, about 11.1 hours. Water productivity is crop output per unit of water: 5,000 kilograms of grain from 450 millimetres over one hectare (4,500 cubic metres) gives about 1.1 kilograms per cubic metre.
Surface irrigation (flooding, basins, borders and furrows) is cheapest to install but loses water to deep percolation and runoff; field application efficiency is typically in the range of about 30 to 60 per cent. Sprinkler irrigation sprays water like rain and usually reaches about 70 to 80 per cent. Drip or micro-irrigation delivers water to the root zone through emitters and often reaches about 90 per cent; it also allows fertigation, the application of soluble fertiliser through the system. Application efficiency is the water stored in the root zone divided by the water applied: if 100 millimetres are applied and 65 millimetres stay in the root zone, efficiency is 65 per cent. Drip suits widely spaced, high-value crops such as fruit trees, vegetables, sugarcane and cotton.
Drainage removes excess water from the root zone. Without it, irrigation raises the water table, causing waterlogging, and evaporation from a shallow water table leaves salt at the surface. Remedies are surface drains, subsurface drains (perforated pipes buried in the field), vertical drainage by pumping tubewells, and bio-drainage with fast-transpiring trees.
A watershed (or catchment) is the land area that drains to a common outlet such as a stream, tank or river point. Because water and soil move downhill, the watershed is the natural unit for managing rainfed land: work begins at the ridge and moves down to the valley. Soil erosion is estimated with the Universal Soil Loss Equation, A = R x K x LS x C x P, where A is soil loss, R the rainfall erosivity, K the soil erodibility, LS the slope length and steepness, C the cover and management factor and P the support practice factor.
Conservation measures fall into three groups. Agronomic measures include contour cultivation, strip cropping, cover crops, mulching and conservation tillage. Engineering measures include contour bunds and graded bunds on gentle slopes, bench terraces on steep slopes, gully plugs, check dams, percolation tanks and farm ponds. Vegetative measures include grass strips and hedges such as vetiver along the contour, and tree planting on degraded land. Runoff that can be harvested is estimated as rainfall depth times catchment area times a runoff coefficient: 800 millimetres falling on 100 hectares with a runoff coefficient of 0.2 yields 0.8 x 1,000,000 x 0.2, or 160,000 cubic metres.
Sukhomajri in Haryana (1970s), where villagers protected the catchment of a small dam in return for shares of its water, and Ralegan Siddhi in Maharashtra are classic Indian cases. In India the watershed component of the Pradhan Mantri Krishi Sinchayee Yojana continues earlier integrated watershed programmes, and NABARD has funded participatory watershed development. Works without local institutions for maintenance and water sharing do not last.
Farm power comes from people, animals, engines, motors and solar energy; power per hectare, a common mechanisation indicator, is far lower in South Asia and Africa than in East Asia or the West. Tractors are rated by engine horsepower or kilowatts and deliver power through the drawbar, the power take-off (PTO) shaft and hydraulics. Two-wheel power tillers suit small and wet fields such as paddies.
Tillage implements are primary or secondary. Primary tillage breaks and turns the soil: the mouldboard plough inverts the furrow slice and buries residue; the disc plough works in hard, stony or trashy soils; the chisel plough and subsoiler break compacted layers without inversion; the rotavator (rotary tiller) pulverises soil in one pass. Secondary tillage prepares a seedbed: harrows, cultivators, levellers and planks. Laser land levellers produce a precisely level field that saves irrigation water and evens out crop stands.
A seed-cum-fertiliser drill places seed and fertiliser in rows at a controlled depth. A zero-till drill sows directly into the previous crop's stubble without ploughing, saving fuel, time and soil. Machines that sow wheat directly into standing rice residue help avoid burning straw in north-west India, where the short gap between combine-harvested rice and wheat sowing has made residue burning a serious air-quality problem. Harvesting moves from sickles to reapers and to combine harvesters, which cut, thresh and clean in one operation. Threshers are a frequent cause of farm injury.
Field capacity is the area a machine covers per hour. Theoretical field capacity in hectares per hour equals working width in metres times speed in kilometres per hour divided by 10. Effective field capacity multiplies this by field efficiency, which allows for turning, overlap and stoppages. A 2-metre implement at 4 kilometres per hour has a theoretical capacity of 0.8 hectares per hour; at 75 per cent field efficiency the effective capacity is 0.6 hectares per hour, so 6 hectares take 10 hours.
Machine costs are fixed or variable. Fixed costs are incurred whether or not the machine works: depreciation, interest on investment, housing, insurance and taxes. Variable or operating costs rise with use: fuel, lubricants, repairs and maintenance, and the operator's wages. Cost per hour falls as annual use rises, so small farms rarely justify owning large machines. The break-even use between owning and hiring is annual fixed cost divided by the difference between the hire rate and the owner's variable cost per hour. If fixed costs are 50,000 a year, the hire rate is 800 an hour and the owner's variable cost is 300 an hour, owning pays only above 100 hours a year. Custom hiring centres let small farmers rent machines by the hour or hectare.
Energy enters farming directly, as diesel, electricity, and human and animal labour, and indirectly, as the energy embodied in fertilisers, pesticides, machinery and irrigation infrastructure. Nitrogen fertiliser is the largest indirect energy input in intensive cropping because ammonia is made by the Haber-Bosch process, which uses natural gas or other fossil fuel as both feedstock and fuel. Energy use efficiency is output energy divided by input energy.
Renewable energy is spreading on farms. Solar water pumps replace diesel pumps and grid connections; India's PM-KUSUM scheme, launched in 2019, supports standalone solar pumps and the solarisation of grid-connected pumps, and in some designs lets farmers sell surplus power. Biogas plants digest cattle dung and other organic waste anaerobically to produce a gas that is mostly methane with carbon dioxide, used for cooking, lighting or engines, and leave a slurry that is a good manure. Flat-rate or free farm power makes the marginal cost of pumping near zero and drives groundwater depletion.
The FAO's State of Food and Agriculture 2019 estimated that around 14 per cent of food is lost between harvest and the retail stage, and UNEP's Food Waste Index Report 2021 estimated that around 17 per cent of food available to consumers is wasted in households, food service and retail. Food loss happens in production, handling, storage and processing; food waste happens at retail and consumption. In low-income countries most loss occurs early in the chain because of poor harvesting, drying, storage and transport; in high-income countries more is wasted by retailers and consumers.
Quality is set at harvest and cannot be improved afterwards, only kept. Harvest at the right maturity is judged by indices such as days from flowering, colour, firmness, total soluble solids, oil content or grain moisture. Physiological maturity ends development; commercial maturity is fitness for the intended market.
Grains must be dried before storage, because moist grain heats, moulds and attracts insects. Cereals are usually stored at about 12 to 14 per cent moisture (wet basis), oilseeds at lower levels, with exact safe limits depending on crop, temperature and storage period. Drying calculations rest on the fact that dry matter does not change: final weight equals initial weight times (100 minus initial moisture) divided by (100 minus final moisture). Drying 1,000 kilograms of paddy from 20 to 14 per cent moisture leaves 1,000 x 80 / 86, about 930 kilograms, so about 70 kilograms of water is removed. Simply subtracting six per cent of the initial weight (giving 940 kilograms) is a common error.
Grain is stored in bags, silos, farm bins and, in India, covered-and-plinth stacks. Major storage insects include the rice weevil (Sitophilus oryzae), the lesser grain borer (Rhyzopertha dominica), the khapra beetle (Trogoderma granarium, a quarantine pest for many importing countries) and pulse beetles (Callosobruchus species). Control combines dry, clean storage, inspection and fumigation, mostly with phosphine. Hermetic bags and silos starve insects of oxygen and are effective for smallholders. Warehouse receipts let farmers borrow against stored grain.
Fresh produce is alive after harvest: it respires, losing sugar and weight, and transpires, losing water and crispness. Respiration roughly doubles or more with each 10 degree rise in temperature, so rapid removal of field heat (pre-cooling by forced air, hydro-cooling or ice) and an unbroken cold chain are the main tools for extending shelf life. Tropical produce such as banana and mango suffers chilling injury if stored too cold, so each product has its own safe temperature. Controlled atmosphere storage lowers oxygen and raises carbon dioxide to slow respiration and is used for apples for many months; modified atmosphere packaging does the same at pack level.
Primary processing makes a commodity storable and saleable: cleaning, drying, dehusking, milling, ginning, pasteurising milk. Secondary processing turns it into an ingredient or food: flour into bread, milk into cheese, fruit into pulp. Tertiary processing produces ready-to-eat and ready-to-cook foods.
In rice milling, paddy loses its husk (about a fifth of paddy weight) and then its bran; milling outturn, the weight of milled rice per unit of paddy, is commonly around two-thirds but depends on variety, drying and mill. Head rice yield, the share of whole kernels, sets the price. Parboiling (soaking, steaming and drying paddy before milling) gelatinises starch, reduces breakage and drives some vitamins from the bran into the grain. Milk is pasteurised either at 63 degrees Celsius for 30 minutes (batch) or at 72 degrees Celsius for 15 seconds (high-temperature short-time), or sterilised by ultra-high temperature treatment for long shelf life.
Food safety rests on good agricultural practices on the farm, good manufacturing practices in the plant, and Hazard Analysis and Critical Control Point (HACCP) systems, which identify hazards and control them at critical points through seven principles. Codex Alimentarius, set up by the FAO and WHO in 1963, publishes international food standards that the WTO's sanitary and phytosanitary agreement treats as reference points. National regulators, such as India's FSSAI under the Food Safety and Standards Act 2006, enforce domestic rules.
Using the Atwater factors, carbohydrate and protein give about 4 kilocalories per gram and fat about 9 (alcohol about 7). A meal with 60 grams of carbohydrate, 10 grams of protein and 15 grams of fat provides 240 + 40 + 135 = 415 kilocalories. Protein quality depends on essential amino acids: cereals are low in lysine and pulses are low in the sulphur amino acids such as methionine, so eating them together gives a better-balanced protein.
Malnutrition includes undernutrition, micronutrient deficiencies and overweight, and many countries now face all three at once, the so-called triple burden. In children, the WHO growth standards define stunting as low height-for-age (below minus two standard deviations of the reference median), the mark of chronic undernutrition; wasting as low weight-for-height, the mark of acute undernutrition; and underweight as low weight-for-age, which combines both. In adults the WHO body mass index cut-offs are below 18.5 for underweight, 25 and above for overweight and 30 and above for obesity. Kwashiorkor, with oedema, is linked mainly to protein deficiency; marasmus, severe wasting, to energy deficiency.
Micronutrient deficiency, called hidden hunger, includes iron deficiency anaemia; vitamin A deficiency causing night blindness and xerophthalmia; iodine deficiency causing goitre and impaired development, prevented by salt iodisation; vitamin C deficiency causing scurvy; vitamin D deficiency causing rickets; thiamine deficiency causing beriberi in populations eating polished rice; and niacin deficiency causing pellagra where maize is the staple without traditional alkali processing. Responses include diverse diets, fortification, supplements and biofortification (zinc wheat, iron pearl millet, orange-fleshed sweet potato).
The World Food Summit of 1996 defined food security as existing when all people, at all times, have physical and economic access to sufficient, safe and nutritious food that meets their dietary needs and food preferences for an active and healthy life. The FAO organises this into four pillars. Availability is the supply of food from production, stocks and net trade. Access is households' ability to obtain food through income, prices, transfers and own production. Utilisation is the body's ability to make good use of food, which depends on diet, water, sanitation and health. Stability means that the other three hold over time, through droughts, price spikes, conflicts and economic shocks. The High Level Panel of Experts has proposed adding agency and sustainability as further dimensions.
Amartya Sen's entitlement approach (Poverty and Famines, 1981) showed that famines such as Bengal in 1943 occurred without a large fall in food availability, because some groups lost the ability to command food: access matters as much as supply. Measures include the FAO prevalence of undernourishment, the eight-question Food Insecurity Experience Scale, dietary diversity scores and anthropometry. The FAO-led State of Food Security and Nutrition in the World reports have placed the number of chronically undernourished people at roughly 700 to 800 million in the mid-2020s. SDG 2 aims to end hunger by 2030.
At national level, the self-sufficiency ratio is production divided by domestic use (production plus imports minus exports). A country producing 100 million tonnes, importing 20 and exporting 10 has a ratio of 100/110, about 91 per cent, and an import dependency ratio of 20/110, about 18 per cent. India's National Food Security Act 2013 covers up to 75 per cent of the rural and 50 per cent of the urban population with subsidised grain through the public distribution system, alongside school meals and child nutrition services.
Agriculture both drives and suffers from climate change. The IPCC Special Report on Climate Change and Land (2019) estimated that the food system as a whole, including production, land-use change, processing, transport and waste, accounts for roughly 21 to 37 per cent of global greenhouse gas emissions. The main farm sources are methane from ruminant digestion and flooded rice, nitrous oxide from fertiliser and manure, and carbon dioxide from clearing forests and draining peatlands. Emissions of different gases are compared as carbon dioxide equivalents using global warming potentials; the values have been revised in each IPCC assessment (for 100 years, methane about 28 in AR5 and about 27 to 30 in AR6, nitrous oxide about 265 in AR5 and 273 in AR6), so a calculation should state which values it uses. With a methane factor of 28, 50 kilograms of methane is 1,400 kilograms of carbon dioxide equivalent.
Responses to heat, erratic rain and new pest ranges fall into adaptation (heat- and drought-tolerant varieties, shifted sowing dates, water harvesting, insurance, diversification) and mitigation (better nitrogen use, alternate wetting and drying in rice, improved feeding and breeding of livestock, agroforestry, reduced deforestation). The FAO's climate-smart agriculture framework has three pillars: sustainably raising productivity and incomes, adapting and building resilience, and reducing emissions where possible. Conservation agriculture rests on three principles: minimum soil disturbance, permanent soil cover with residues or cover crops, and crop diversification through rotations. Organic, natural and regenerative farming results vary widely by crop and region and remain debated.
The model many national research systems followed is the United States land-grant system: the Morrill Act of 1862 granted land to found agricultural colleges, the Hatch Act of 1887 funded experiment stations, and the Smith-Lever Act of 1914 created the cooperative extension service, so that teaching, research and extension were joined in one university.
India's apex body is the Indian Council of Agricultural Research (ICAR), set up in 1929 as the Imperial Council of Agricultural Research and now under the Department of Agricultural Research and Education (DARE). ICAR runs national institutes and coordinated projects and coordinates the state agricultural universities (SAUs). The first SAU, at Pantnagar in Uttarakhand (then Uttar Pradesh), opened in 1960 on the land-grant model. Krishi Vigyan Kendras (farm science centres), the first opened at Puducherry in 1974, test and demonstrate technology at district level. Public extension in the states is coordinated at district level through the Agricultural Technology Management Agency (ATMA).
Internationally, the CGIAR, founded in 1971, groups research centres including IRRI (rice, Los Baños, Philippines, founded 1960), CIMMYT (maize and wheat, Mexico), ICRISAT (dryland crops, near Hyderabad, India), IITA (Ibadan, Nigeria), ILRI (livestock, Nairobi), CIP (potato, Lima), IFPRI (food policy, Washington) and the Alliance of Bioversity International and CIAT. The FAO (founded 1945, headquarters Rome), the International Fund for Agricultural Development and the World Food Programme are the three Rome-based UN food agencies. Norman Borlaug received the Nobel Peace Prize in 1970 for the high-yielding wheat work that underpinned the Green Revolution.
Extension moved from World Bank-promoted Training and Visit (1970s) to Farmer Field Schools (FAO, Indonesia, late 1980s, rice IPM) and now pluralistic, digital extension.
In the first term you use this subject to make sense of every later course. When marketing management talks about the seed or fertiliser trade you need to know seed classes and fertiliser grades; when finance appraises a dairy loan you need gestation, lactation and calving interval; when supply-chain courses discuss cold chains you need respiration and chilling injury. For the entrance and recruitment exams, drill the scientific names, seasons, deficiency symptoms, pests and diseases of the named crops, livestock breeds and diseases, and the institutions with their dates. Practise every worked calculation in this manual until you can do it in under a minute: fertiliser product from nutrient, seed rate, cropping intensity, irrigation volume and time, field capacity, drying loss, FCR and food energy.
Five years into an agribusiness career you use this knowledge to check what field staff and suppliers tell you. An input-company area manager plans dealer stocks from crop calendars and recommended doses, and explains to dealers why balanced NPK and zinc pay. A bank agricultural officer sets the scale of finance for a crop, checks whether a dairy unit's projected milk yield is realistic given breed and calving interval, and recognises when a loan proposal assumes impossible yields. A procurement manager in a food company specifies moisture, aflatoxin and residue limits, judges harvest maturity, and plans storage to avoid weevil and moisture losses. You also need to talk with agronomists and veterinarians without being misled.
With twenty-five years of experience the questions become portfolio and policy questions. A senior banker decides how much of a lending book to place in irrigated rice-wheat districts versus rainfed pulse areas, weighing groundwater decline and climate risk. A food company's sourcing head decides whether to build contract farming with seed, extension and residue testing, or to buy on the spot market, and where to put cold storage and processing plants given loss points along the chain. A development finance leader chooses between watershed, micro-irrigation and livestock health programmes for the greatest effect on incomes and food security. These decisions rest on the same biology and engineering, applied at scale and against trade, regulatory and climate trends.
A researcher with long field experience works on the open questions: why yield gaps persist where technology is available; how much of the gap is biophysical, managerial or economic; how conservation agriculture, alternate wetting and drying or natural farming perform across sites and years; how to measure food loss consistently along chains; how livestock emission intensity changes with productivity; and how institutions such as producer organisations, warehouse receipts or digital extension change adoption. The work joins crop and animal science with economics and requires careful measurement, a good grasp of the agronomic literature, and the humility to say when results do not generalise beyond the sites studied.
This manual does not give variety-by-variety recommendations, pesticide or veterinary drug doses, or state-specific fertiliser schedules, because these change by region, year and label; follow the local university package of practices and product labels. Fisheries, sericulture, apiculture and mushroom production are mentioned only in passing. Statistics on production, trade shares, GDP shares and undernourishment are given as rounded orders of magnitude and should be refreshed from FAOSTAT, the Economic Survey and SOFI before use. Crops outside the eight named in the syllabus (maize, cotton, millets, soybean, potato, banana and others) are covered only where they illustrate a general point. Farming-systems typologies for Latin America and the former Soviet Union are treated briefly.
Original practice questions written to the syllabus and pattern of the exams named in each question's examTags. They are not past papers and do not reproduce any board's questions.
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