PSEB SS Agriculture flashcards
PSEB SS Agriculture · Build recall with a focused review session.
33 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Loam soil
- A balanced mixture of about 40% sand, 40% silt and 20% clay; it drains well, holds moisture and nutrients, and suits most field crops.
- Cation exchange capacity
- The soil's capacity to hold exchangeable cations such as calcium, magnesium and potassium on clay and organic matter surfaces; higher CEC means better nutrient retention.
- Liebig's law of the minimum
- Crop yield is governed by the essential nutrient present in shortest supply relative to need; supplying other nutrients cannot raise yield until that limiting factor is corrected.
- Green manuring
- Growing a leafy legume such as dhaincha or sunhemp and ploughing it into the soil before flowering to add organic matter and nitrogen, typically 40–60 kg N per hectare.
- Kharif season
- The monsoon cropping season, with sowing from June to July and harvest in autumn; typical crops include rice, maize, cotton and groundnut.
- Rabi season
- The winter cropping season, sown from October to November and harvested in spring; wheat, mustard and gram are typical rabi crops.
- Critical period of weed competition
- The crop growth interval during which weed infestation most reduces yield; for most annual field crops it falls in roughly the first 30–45 days after sowing.
- Integrated pest management
- A control strategy combining cultural, mechanical, biological and chemical methods, with pesticide use decided by economic threshold levels rather than calendar spraying.
- Economic threshold level
- The pest population density at which control measures are justified because the value of crop loss avoided equals or exceeds the cost of treatment.
- Disease triangle
- The principle that an epidemic requires three interacting factors: a susceptible host, a virulent pathogen and environmental conditions favourable to the pathogen.
- Seed germination percentage
- A quality measure calculated as the number of seeds germinated divided by the total seeds set, multiplied by 100, counted at the standard test period for that crop.
- Seed dormancy
- A resting state in which viable seeds fail to germinate even under favourable conditions; broken by scarification, chilling stratification or gibberellic acid treatment.
- IW/CPE ratio
- Irrigation scheduling rule comparing irrigation water depth to cumulative pan evaporation; irrigation is applied when evaporation reaches 50–75 mm, supplying 4–6 cm water.
- Drip irrigation
- A method delivering water drop by drop near the plant root zone through emitters; it saves roughly 40–60% water compared with flood irrigation and suits wide-row crops.
- Water requirement of a crop
- The total water a crop needs over its season, measured as evapotranspiration; irrigation requirement equals water requirement minus effective rainfall and stored soil water.
- Soil profile horizons
- Vertical soil layers named O for organic litter, A for fertile topsoil, B for subsoil accumulation, C for weathered parent material and R for bedrock.
- Soil erosion types
- Sheet erosion removes a thin uniform layer, rill erosion cuts small channels, gully erosion forms deep channels, and wind erosion removes loose surface soil.
- Reclamation of sodic soil
- Sodic soils with high exchangeable sodium are treated by applying gypsum, then leaching soluble salts through the profile with good-quality water and drainage.
- Leaching for saline soils
- Saline soils are reclaimed by applying excess good-quality water to push soluble salts below the root zone, which requires adequate subsurface drainage.
- Organic carbon in soil
- A soil-test measure of organic matter content; higher organic carbon improves structure, water-holding capacity and microbial activity, and is reported alongside N, P, K and pH.
- Gross income
- The total value of all produce from a farm or enterprise in a season, before any cost is deducted; net income equals gross income minus total cost.
- Fixed costs
- Farm expenses that do not change with output level, such as land revenue, depreciation on machinery and interest on land; they are incurred whether or not a crop is grown.
- Variable costs
- Farm expenses that change with the level of production, including seed, fertilizer, hired labour and irrigation charges; they are avoidable if the enterprise is not taken up.
- Benefit–cost ratio
- Gross returns divided by total cost of the enterprise; a value greater than one indicates that returns exceed costs and the enterprise is profitable.
- Cropping intensity
- Gross cropped area divided by net sown area, multiplied by 100; it exceeds 100 when more than one crop is harvested from the same land in a year.
- Operational holding
- The land actually managed and farmed by a household, whether owned, leased or otherwise held; it is the unit used in agricultural census farm-size classification.
- Extension teaching methods
- Classified as individual (farm visit, office call), group (method demonstration, field day) and mass (radio, poster, campaign), chosen by audience size and learning objective.
- Institutional agricultural credit
- Loans for farming from cooperative banks, commercial banks and regional rural banks, generally carrying lower interest and longer repayment terms than moneylender credit.
- Minimum support price
- A price announced by government before the sowing season, guaranteeing purchase of specified crops at that rate to protect farmers from a market price crash.
- Basal fertilizer application
- Applying the full phosphorus and potassium dose plus part of the nitrogen at sowing, with remaining nitrogen split at tillering and later growth stages.
- Seed inoculation with Rhizobium
- Treating legume seed with Rhizobium culture before sowing so root nodules form and fix atmospheric nitrogen; Azotobacter is used similarly for non-legume cereals.
- Post-harvest grain drying
- Reducing grain moisture to about 12–14% before storage, which limits mould growth and insect attack and lowers storage losses.
- Pre-harvest interval
- The waiting period stated on a pesticide label between the last spray and harvest; it must be observed to keep residues within permitted limits.