PSEB SS Agriculture cheat sheet

Soil texture classes follow the sand–silt–clay triangle: loam holds roughly 40% sand, 40% silt, 20% clay and is considered best for general field crops.

Soil pH 6.5–7.5 is the optimum range for most cereals; below 5.5 apply lime, above 8.0 apply gypsum, both calculated from soil-test values before sowing.

Essential plant nutrients: 17 total - macronutrients N, P, K, Ca, Mg, S; micronutrients Fe, Mn, Zn, Cu, B, Mo, Cl, Ni.

Law of minimum (Liebig): yield is limited by the nutrient in shortest supply relative to need, so adding other nutrients cannot compensate.

NPK dose is split: full P and K at sowing as basal; N in 2–3 splits at sowing, tillering and panicle/flowering stage to cut leaching loss.

Green manuring with dhaincha or sunhemp fixes 40–60 kg N/ha; Rhizobium seed inoculation suits pulses, Azotobacter suits cereals.

Crop rotation with a legume restores nitrogen and breaks pest–disease cycles; continuous monocropping raises soil-borne pathogen load.

Irrigation scheduling by IW/CPE ratio: irrigate when cumulative pan evaporation reaches 50–75 mm, giving 4–6 cm water per irrigation.

Weed control follows critical period of crop–weed competition: roughly the first 30–45 days after sowing for most annual field crops.

Kharif crops (rice, maize, cotton, groundnut) are sown June–July with monsoon; rabi crops (wheat, mustard, gram) are sown October–November.

Seed rate and spacing are crop-specific: wheat about 100 kg/ha at 22.5 cm rows; rice nursery about 20–25 kg/ha for transplanting.

Seed germination test: percentage germination = (number of seeds germinated ÷ total seeds set) × 100, counted at the standard test period for the crop.

Seed dormancy is broken by scarification, stratification (chilling), or gibberellic acid treatment depending on the cause of dormancy.

Pest control follows integrated pest management: cultural, mechanical, biological and chemical methods in that order, with economic threshold level guiding sprays.

Major insect pests: stem borer in rice and maize, aphid in mustard, bollworm in cotton, and termites in rainfed crops; identify by damage symptom before spraying.

Plant disease diagnosis uses the disease triangle: susceptible host, virulent pathogen and favourable environment must all be present.

Fungicide and insecticide labels state dose, waiting period and pre-harvest interval; the waiting period must be respected to avoid residue.

Post-harvest losses are cut by drying grain to 12–14% moisture before storage and by fumigating godowns against stored-grain pests.

Soil profile horizons: O (organic litter), A (topsoil, most fertile), B (subsoil accumulation), C (weathered parent material), R (bedrock).

Cation exchange capacity (CEC) rises with clay and organic matter; soils with CEC below 10 cmol/kg need frequent small fertilizer doses.

Organic matter improves water-holding capacity, structure and microbial activity; FYM at 10–20 t/ha is a common basal organic dose.

Soil erosion types: sheet, rill, gully and wind erosion; contour ploughing, terracing and bunding are the standard control measures.

Water requirement of a crop = evapotranspiration over the season; irrigation requirement = water requirement minus effective rainfall and soil-stored water.

Drip irrigation saves 40–60% water versus flood irrigation and suits wide-row crops; sprinkler suits close-growing crops on undulating land.

Drainage removes excess water; waterlogging causes oxygen deficiency in roots and raises risk of denitrification losses.

Soil testing reports N, P, K, pH, organic carbon and electrical conductivity; fertilizer recommendation is adjusted by soil-test rating (low, medium, high).

Saline soils are reclaimed by leaching with good-quality water plus drainage; sodic soils need gypsum followed by leaching.

Farm income measures: gross income = total value of produce; net income = gross income − total cost; farm profit includes unpaid family labour valuation.

Cost concepts: fixed costs (land revenue, depreciation, interest) do not vary with output; variable costs (seed, fertilizer, labour, irrigation) do.

Benefit–cost ratio = gross returns ÷ total cost; a ratio above 1 means the enterprise is profitable.

Cropping intensity = (gross cropped area ÷ net sown area) × 100; it exceeds 100 when more than one crop is grown per year on the same land.

Farm size classes and landholding data come from agricultural censuses; operational holding is the land actually managed by the farmer.

Extension teaching methods: individual (farm visit, office call), group (demonstration, field day) and mass (radio, poster, campaign).

Agricultural credit sources: institutional (cooperative banks, commercial banks, RRBs) and non-institutional (moneylenders); institutional credit carries lower interest.

Crop insurance and minimum support price protect farmers against yield loss and price crash; MSP is announced before the sowing season.

Farm records and accounts (cash book, ledger, inventory) are the basis for computing cost of cultivation and evaluating enterprise performance.