WBCHSE HS Vocational Agriculture flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Cation Exchange Capacity

The total quantity of exchangeable cations a soil can hold, expressed in centimoles of charge per kilogram. It rises with clay and organic matter, increasing nutrient retention.

Law of the Minimum

Plant growth is governed by the nutrient present in shortest supply relative to need. Supplying other nutrients in excess cannot raise yield beyond that limiting factor.

C3 versus C4 plants

C3 plants fix carbon with RuBisCO and photorespire readily; C4 plants use PEP carboxylase, concentrate CO2, and achieve higher water-use efficiency in hot, bright conditions.

Kharif and rabi seasons

Kharif crops such as rice and maize are sown with monsoon onset; rabi crops such as wheat and mustard are sown in winter. The terms describe seasonal cropping calendars.

Grafting

A propagation technique joining a scion (desired shoot) to a rootstock so they unite and grow as one plant. It is used in mango, citrus and other horticultural crops.

Intercropping

Growing two or more crops simultaneously in the same field in distinct rows or strips. It spreads risk and uses light, water and nutrients more completely than sole cropping.

Universal Soil Loss Equation

A = R × K × LS × C × P estimates average annual soil loss, combining rainfall erosivity, soil erodibility, slope length and steepness, cover management and support practice factors.

Contour bunding

Constructing earthen bunds along contour lines on sloping land. Bunds intercept runoff, reduce slope length and velocity, and trap soil, conserving both soil and moisture.

Duty of water

The area of land irrigated per unit volume of water, commonly expressed in hectares per cubic metre per second. It reflects irrigation efficiency over a season.

Drip irrigation

Applying water slowly and directly to the root zone through emitters. It minimises evaporation and deep percolation and permits fertigation, giving high water-use efficiency.

Power take-off

A splined shaft on a tractor that transmits engine power to driven implements such as rotavators, threshers and pumps at a standard rotational speed.

Rumen fermentation

Microbes in the rumen break down cellulose and other feed into volatile fatty acids and microbial protein. Rumination and eructation manage fibre breakdown and gas.

Pasteurisation of milk

Heating milk to about 63 degrees Celsius for 30 minutes or 72 degrees for 15 seconds, then rapidly cooling it to destroy pathogenic bacteria while retaining quality.

Composite fish culture

Stocking surface, column and bottom feeding fish species together in one pond so that natural food at all depths is used, raising total yield per unit area.

Induced breeding in fish

Injecting pituitary extract or synthetic hormone to stimulate spawning in fish that will not breed naturally in confined ponds, enabling reliable seed production.

Break-even point

The output level at which total revenue equals total cost, calculated as fixed cost divided by selling price per unit minus variable cost per unit.

Value addition

Processing raw farm produce into products such as paneer, flour, jam or oil. It raises margin per unit, extends shelf life and creates off-season income.

Gross margin

Gross return from a crop or enterprise minus its variable costs. It measures enterprise profitability when fixed costs are shared and cannot be allocated precisely.

Marketable surplus

Total farm production minus family consumption, seed, feed and other on-farm requirements. It is the quantity actually available for sale in the market.

Economic threshold level

The pest population density at which control action is justified because further increase would cause economic loss exceeding the cost of treatment.

Disease triangle

A plant disease develops only when a susceptible host, a virulent pathogen and favourable environmental conditions coincide. Removing any one component prevents the disease.

Trichogramma

A tiny parasitic wasp that lays eggs inside the eggs of moths and borers, destroying them. It is widely released as a biological control agent in field crops.

Seed germination percentage

The proportion of tested seeds producing normal seedlings under specified conditions, expressed as a percentage and used to judge seed quality and sowing rate.

Randomised block design

A field layout in which treatments are replicated in blocks that capture site variation, with treatments randomly assigned within each block to reduce experimental bias.

Soil sampling pattern

Collecting subsamples in a zigzag or grid pattern across a field, mixing them into one composite sample that represents the field for laboratory analysis.

Mulching

Covering the soil surface with crop residue, plastic or other material to reduce evaporation, suppress weeds, moderate temperature and protect against raindrop impact.

Fertigation

Injecting soluble fertilizers into drip irrigation water so nutrients reach the root zone in small, frequent doses, improving nutrient-use efficiency and reducing leaching.

Balanced ration

A feed mixture supplying energy, protein, minerals, vitamins and water in proportions that meet an animal's maintenance and production requirements without excess or deficiency.

Integrated pest management

A strategy combining cultural, mechanical, biological and chemical controls, using pesticides only when pest density exceeds the economic threshold level.

Working capital

Funds needed for day-to-day farm or enterprise operations such as seed, fertilizer, feed and labour, recovered within a single production cycle.

Cooperative marketing

Farmers pooling produce to sell collectively, improving bargaining power, reducing dependence on middlemen and allowing better grading, storage and price realisation.

Pond liming

Applying lime to fish ponds to raise alkalinity, stabilise pH, improve nutrient availability and reduce disease outbreaks before stocking and during culture.