BSEB Inter Agriculture cheat sheet

Cropping intensity (%) = (sum of areas cropped in a year ÷ net sown area) × 100; a sequence of two crops on the same land gives 200%.

Land equivalent ratio (LER) = sum of (intercrop yield of each component ÷ its sole-crop yield); LER > 1 indicates an intercropping advantage.

Crop period = days from sowing to harvest; growing degree days (GDD) = Σ[(Tmax + Tmin)/2 − Tbase], with Tbase commonly 10 °C for wheat and 10–15 °C for maize.

C3 plants (rice, wheat) photorespire and suit cooler, humid climates; C4 plants (maize, sorghum, sugarcane) have lower CO2 compensation points and higher water-use efficiency.

Critical period of crop–weed competition is generally the first 30–45 days after sowing; delaying weeding beyond this causes irreversible yield loss.

Tillage operations: primary tillage (ploughing) breaks compacted soil; secondary tillage (harrowing, levelling) prepares a fine seedbed; zero tillage retains residues and conserves moisture.

Seed rate (kg/ha) = (desired plant population per ha × test weight in g) ÷ (1000 × germination % × purity % × field establishment %).

Water requirement = evapotranspiration + percolation + other unavoidable losses; irrigation scheduling by IW/CPE ratio around 0.8–1.0 for many field crops.

Soil texture classes follow the percentage of sand, silt and clay; loam is roughly balanced, while clay soils hold more water and nutrients but drain slowly.

Bulk density (g/cm³) = oven-dry soil mass ÷ total soil volume; particle density is about 2.65 g/cm³, so porosity (%) = (1 − bulk density/2.65) × 100.

Soil pH governs nutrient availability: most field crops perform best at pH 6.0–7.5; acidity is corrected with lime, alkalinity with gypsum.

Cation exchange capacity (CEC) measures the soil's ability to hold exchangeable cations; high-clay and high-organic-matter soils have higher CEC.

Essential macronutrients: N, P, K, Ca, Mg, S; micronutrients: Fe, Mn, Zn, Cu, B, Mo, Cl, Ni.

Fertilizer dose example: a 100 kg/ha N recommendation can be met with about 217 kg/ha urea (46% N); P is expressed as P2O5 and K as K2O in fertilizer grades.

Law of the minimum: yield is limited by the nutrient in shortest supply; Liebig's law justifies balanced fertilization rather than excess of one nutrient.

Organic matter improves structure, water-holding capacity and microbial activity; the C:N ratio near 10:1 favours rapid decomposition, wide ratios immobilize nitrogen.

Pure-line selection is used in self-pollinated crops; mass selection is common in cross-pollinated crops.

Hybridization types: single cross (A × B), double cross [(A × B) × (C × D)], three-way cross [(A × B) × C], and top cross (line × tester).

Heterosis (hybrid vigour) is the superiority of F1 over parents; it is highest in cross-pollinated crops and exploited commercially in maize and sorghum.

Backcross breeding transfers a single gene (e.g., disease resistance) into a recurrent parent; six or more backcrosses are typically needed.

Mutation breeding uses physical (X-rays, gamma rays) or chemical (EMS) mutagens; induced mutants are useful when natural variation is absent.

Male sterility (cytoplasmic, genetic or cytoplasmic–genetic) enables hybrid seed production without hand emasculation.

Self-incompatibility prevents self-fertilization; it is exploited in hybrid seed production of brassicas.

Varietal release requires distinctness, uniformity and stability (DUS) testing plus multi-location yield trials.

Seed germination (%) = (number of normal seedlings ÷ number of seeds sown) × 100; purity (%) = (pure seed weight ÷ total sample weight) × 100.

Seed viability is tested by tetrazolium (TZ) staining; live embryos stain red, dead tissue remains unstained.

Seed dormancy can be broken by scarification, stratification (cold treatment), or gibberellic acid application.

Mendel's law of segregation: alleles separate during gamete formation; law of independent assortment applies to genes on different chromosomes.

Monohybrid F2 ratio 3:1; dihybrid F2 ratio 9:3:3:1; test cross ratio 1:1 reveals heterozygosity.

Seed moisture content governs storability; orthodox seeds store best at low moisture and low temperature, recalcitrant seeds (e.g., mango, jackfruit) cannot be dried.

Seed certification classes: breeder seed, foundation seed, registered seed, certified seed; each generation must meet field and laboratory standards.

Seed treatment with fungicides or bioagents (Trichoderma, Rhizobium) protects germination and improves establishment.

Vegetables are grouped by botany and climate: cole crops (cabbage, cauliflower), root crops (carrot, radish), solanaceous (tomato, brinjal), cucurbits (cucumber, pumpkin).

Vegetative propagation methods: cutting, layering (air layering for guava, litchi), grafting (mango, citrus), budding (rose, ber).

Pruning and training regulate canopy light and fruit quality; heading back and thinning out are the two basic pruning cuts.

Fruit crops are classified as tropical (mango, banana), subtropical (citrus, guava), and temperate (apple, pear, peach).

Floriculture crops: rose, chrysanthemum, marigold, gladiolus, tuberose; bulbous crops are propagated by corms, bulbs or tubers.

Post-harvest handling includes grading, pre-cooling, packaging and cold storage; ethylene accelerates ripening and senescence.

Kitchen garden planning: quick-growing leafy vegetables near the house, tall crops on the north side to avoid shading.

Protected cultivation (polyhouse, shade net) extends growing seasons and improves quality of high-value vegetables and flowers.

Insect mouthparts determine control: chewing insects (caterpillars) respond to stomach poisons; sucking insects (aphids, whiteflies) need systemic or contact insecticides.

Economic threshold level (ETL) is the pest density at which control measures are justified to prevent economic loss.

IPM components: cultural, mechanical, biological, chemical and legal methods; chemical control is the last resort.

Common diseases: blight (Alternaria), rust (Puccinia), smut (Ustilago), wilt (Fusarium), bacterial blight (Xanthomonas), and viral diseases transmitted by vectors.

Koch's postulates establish that a microorganism causes a disease: isolation, pure culture, inoculation, re-isolation.

Fungicides: protectants (mancozeb, copper oxychloride) prevent infection; systemics (carbendazim, triadimefon) act inside plant tissue.

Biological control agents: Trichoderma (soil-borne pathogens), Bacillus thuringiensis (lepidopteran larvae), NPV (Helicoverpa).

Pesticide safety: observe pre-harvest interval, wear protective clothing, and avoid spraying during flowering to protect pollinators.

Dairy cattle breeds: exotic (Holstein-Friesian, Jersey), indigenous (Sahiwal, Red Sindhi, Gir), and crossbreds for higher milk yield.

Milk composition: water about 87%, fat 3.5–4.5%, protein 3.2–3.5%, lactose 4.5–5.0%, minerals about 0.7%.

Clean milk production: wash udder, use clean utensils, cool milk quickly, and maintain hygienic milking practices.

Feed classification: roughages (green fodder, hay, straw) and concentrates (oil cakes, grains, bran); balanced ration supplies energy, protein, minerals and vitamins.

Common cattle diseases: foot-and-mouth disease (viral), mastitis (bacterial), anthrax (bacterial), and parasitic infestations.

Vaccination schedules and deworming are essential health management tools; colostrum feeding within the first hour protects newborn calves.

Poultry: layers for egg production, broilers for meat; incubation period of chicken eggs is 21 days.

Animal breeding methods: inbreeding, outcrossing, crossbreeding and grading up; artificial insemination is widely used in cattle.

Farm income = gross income − total cost; net profit = gross income − (variable cost + fixed cost).

Cost concepts: fixed cost (land rent, depreciation) and variable cost (seed, fertilizer, labour); total cost is the sum of both.

Benefit–cost ratio (BCR) = present value of benefits ÷ present value of costs; BCR > 1 means the project is profitable.

Law of diminishing returns: as one input increases with others fixed, marginal returns eventually decline.

Demand and supply determine price; price elasticity of demand measures responsiveness of quantity demanded to price changes.

Marketing channels and margins: the difference between producer price and consumer price includes transport, storage and trader margins.

Credit sources: institutional (cooperative banks, RRBs, commercial banks) and non-institutional (moneylenders); interest rates and repayment terms matter.

Farm planning uses budgeting and linear programming to allocate land, labour and capital for maximum returns.

Extension teaching methods: individual (farm visit, office call), group (demonstration, meeting), and mass (radio, TV, print).

Adoption process: awareness, interest, evaluation, trial and adoption; innovators adopt first, laggards last.

Diffusion of innovations: the adoption curve is roughly normal, with innovators, early adopters, early majority, late majority and laggards.

Farm records: physical (land, livestock, machinery) and financial (cash book, ledger, inventory); records support decision-making and credit access.

Farm management functions: planning, organizing, directing, coordinating and controlling.

Demonstration plots compare improved practice with farmer practice; result demonstrations show local proof of technology.

Communication elements: sender, message, channel, receiver and feedback; barriers include language, illiteracy and lack of trust.

Participatory approaches (farmer field schools, group discussions) improve technology uptake and ownership.

Tractor power take-off (PTO) transmits engine power to implements; PTO speed is standardized near 540 rpm at rated engine speed.

Draft requirement depends on soil type, implement width and depth; lighter soils require less draft.

Field capacity: theoretical field capacity = (width × speed)/10 for width in metres and speed in km/h, giving ha/h.

Field efficiency (%) = (actual field capacity ÷ theoretical field capacity) × 100.

Irrigation methods: surface (flood, furrow), sprinkler, and drip; drip irrigation saves water and reduces weed growth.

Farm machinery maintenance: lubrication, cleaning, adjustment and timely replacement of worn parts extend machine life.

Grain storage structures must control moisture, temperature and pests; hermetic storage reduces insect damage.

Soil and water conservation structures: contour bunds, terraces, check dams and grassed waterways reduce erosion.

Agroforestry is the deliberate integration of trees with crops and/or livestock on the same land unit.

Common systems: agrisilviculture (trees + crops), silvopasture (trees + pasture/livestock), agrosilvopasture (trees + crops + livestock), and alley cropping.

Nitrogen-fixing trees (Leucaena, Gliricidia, Sesbania) improve soil fertility through biological nitrogen fixation.

Multipurpose trees provide fuelwood, fodder, fruit and timber while moderating microclimate.

Tree–crop competition for light, water and nutrients must be managed by pruning, spacing and root barriers.

Windbreaks and shelterbelts reduce wind erosion and protect crops and livestock.

Agroforestry improves soil organic matter, water infiltration and biodiversity while diversifying farm income.

Social forestry includes farm forestry, community forestry and urban forestry for environmental and economic benefits.

Sustainable agriculture balances productivity, profitability and environmental protection for future generations.

Conservation agriculture principles: minimum soil disturbance, permanent soil cover, and crop diversification.

Greenhouse gases from agriculture: methane (livestock, paddy), nitrous oxide (fertilizer), and carbon dioxide (deforestation).

Soil erosion types: sheet, rill, gully and wind erosion; contour farming and terracing reduce water erosion.

Integrated nutrient management combines organic manure, biofertilizers and chemical fertilizers for balanced nutrition.

Water conservation: rainwater harvesting, check dams and mulching reduce runoff and improve moisture retention.

Biodiversity conservation in agriculture includes crop rotation, mixed cropping and habitat preservation for pollinators.

Organic farming avoids synthetic inputs; certification requires a conversion period and documented practices.

Seedbed preparation: ploughing, harrowing, levelling and compaction produce a fine tilth for uniform germination.

Transplanting: seedlings are raised in nursery beds and transplanted at the right age with proper spacing and irrigation.

Weeding methods: manual, mechanical, chemical and biological; timely weeding prevents yield loss.

Fertilizer application methods: broadcasting, band placement, drilling and fertigation; band placement improves nutrient-use efficiency.

Irrigation scheduling by soil moisture or crop stage prevents both water stress and waterlogging.

Pest scouting: regular field inspection detects pests and diseases early; record observations for timely action.

Harvesting and threshing: harvest at physiological maturity, dry to safe moisture, and store in clean, dry conditions.

Farm safety: use protective gear while handling chemicals and operate machinery according to safety guidelines.