Assam ASSEB Higher Secondary Skill Subject Agriculture key terms

The ratio of total cropped area to net sown area in a year, usually expressed as a percentage. A value above 100% shows that land grows more than one crop annually.

The pattern in which crops are grown on a farm over space and time, including their sequence, intercropping arrangement and management practices, chosen to match soil, climate, water and market conditions.

Growing two or more crops on the same field in one agricultural year, either in sequence or together. It raises output per unit area but demands more nutrients, water and labour.

Growing two or more crops simultaneously in the same field in a definite row arrangement, so that the crops compete and complement each other. Legume-cereal mixtures are common because legumes add nitrogen.

Growing different crops in a planned sequence on the same field over successive seasons. Alternating cereals with legumes or deep-rooted crops helps maintain fertility, breaks pest cycles and reduces soil erosion.

The total quantity of exchangeable cations a soil can hold on its clay and organic matter surfaces, expressed in centimoles of charge per kilogram. Higher CEC means greater nutrient retention and buffering.

The percentage of the soil's cation exchange capacity occupied by basic cations such as calcium, magnesium, potassium and sodium rather than acidic ions. High base saturation generally indicates a fertile, less acidic soil.

A measure of the acidity or alkalinity of the soil solution on a scale from 0 to 14. It controls nutrient availability, microbial activity and the choice of crops and amendments.

The amount of agricultural lime needed to raise soil pH to a target level for a chosen crop. It is estimated from soil texture, organic matter and the measured pH of the buffer solution.

The decomposed and decomposing plant and animal residues in soil, together with living microbial biomass. It improves structure, water holding, nutrient supply and cation exchange capacity.

Growing a quick-growing crop, often a legume, and ploughing it into the soil while still green to add organic matter and nitrogen. It improves structure and fertility, especially on light soils.

Supplying crop nutrients through a combination of chemical fertilizers, organic manures, biofertilizers and crop residues, matched to soil test values and crop demand to sustain yields without degrading soil.

The pest population density at which the cost of control measures equals the value of the crop loss they prevent. Control is justified only when the pest population reaches or exceeds this level.

A decision-based approach that combines cultural, mechanical, biological and chemical tactics to keep pest populations below economic thresholds, with pesticides used only as a last resort.

Suppressing pests using their natural enemies, such as predators, parasitoids and pathogens. It includes conservation, augmentation and classical introduction of these agents into the crop ecosystem.

The inherited ability of a pest population to survive doses of an insecticide that would normally kill it, developing after repeated exposure. Rotating chemical groups and following thresholds slow its build-up.

A set of four criteria used to prove that a particular microorganism causes a specific disease: it must be found in all diseased plants, isolated in pure culture, reinoculated to reproduce symptoms, and re-isolated from the new host.

A model showing that an infectious plant disease develops only when a susceptible host, a virulent pathogen and favourable environmental conditions occur together, often extended to include human activity and time.

A prepared raised or flat area of soil where vegetable seedlings are raised before transplanting. It needs fine tilth, drainage, partial shade and protection from pests and heavy rain.

Moving seedlings raised in a nursery to the main field at the right stage of growth. Careful handling, soil moisture and hardening of seedlings before lifting improve establishment and survival.

Gradually exposing nursery seedlings to harsher conditions by reducing water and shade before transplanting. It thickens tissues and improves survival and early growth in the field.

Deliberate removal of plant parts such as shoots, branches or roots to shape growth, improve light penetration, remove diseased wood and balance vegetative growth with flowering and fruiting.

Directing the growth of a plant into a desired framework or shape by tying, staking or selective cutting, so that the canopy receives adequate light and orchard operations become easier.

A feed mixture that supplies all the nutrients an animal needs in the correct proportions for its age, weight and level of production, usually combining roughages with concentrates and mineral supplements.

Feedstuffs low in fibre and high in digestible energy or protein, such as grains, oilseed cakes and bran, used to supplement roughages and support higher milk or growth production.

The amount of feed consumed divided by the live weight gained or product produced over a period. A lower ratio indicates more efficient use of feed and better profitability.

Treating livestock and poultry with an anthelmintic drug to remove internal parasites such as roundworms and flukes. Regular schedules, based on body weight, improve growth and feed efficiency.

A planned timetable for administering vaccines to animals or birds at specified ages, such as against Newcastle disease or foot-and-mouth disease, to build immunity before exposure to infection.

Practices that prevent the entry and spread of disease organisms on a farm, including restricting visitors, disinfecting footwear and vehicles, controlling rodents and isolating newly introduced animals.

A splined shaft at the rear of a tractor that transmits engine power to implements such as threshers, sprayers and pumps, usually running at a standard speed proportional to engine speed.

A linkage with two lower arms and one upper arm that attaches implements to a tractor. It controls working depth and lifts the implement hydraulically for transport.

The horizontal force an implement exerts on a tractor while being pulled through soil or crop. It depends on soil condition, implement width, depth of operation and speed.

The crop yield or biomass produced per unit of water used, whether measured as crop per unit of irrigation water or per unit of evapotranspiration. It guides efficient irrigation scheduling.

Applying water slowly and directly to the root zone through emitters in tubes laid along crop rows. It saves water, reduces weed growth and allows fertilizer to be applied with irrigation.

The growth stage at which water shortage causes the greatest reduction in yield, such as flowering or grain filling. Irrigating at these stages gives the best return per unit of water.

Gross income from a crop or enterprise minus its variable costs. It measures the return to fixed resources and helps compare alternative enterprises on a farm.

The ratio of total returns to total costs of an enterprise or practice. A value above one indicates that returns exceed costs, and higher values indicate more profitable use of resources.

The level of output or price at which total revenue equals total cost, so the enterprise makes neither profit nor loss. It helps farmers decide the minimum scale or price needed.

The portion of a farm's production that remains after family consumption, seed, feed and wastage are set aside, and which is available for sale. It determines the farmer's cash income.

Farmers pooling their produce to sell collectively through a cooperative society, gaining better prices, grading, storage and bargaining power than selling individually in small lots.

A non-formal educational process that helps rural people acquire knowledge, skills and attitudes needed to solve their own problems and improve farm and home practices through voluntary learning.

A teaching method in which a new practice is shown and carried out on a farmer's field or in a village so that people can observe results directly and gain confidence to adopt it.

The mental sequence a person passes through from first hearing of an innovation to finally using it regularly, commonly described as awareness, interest, evaluation, trial and adoption.

Organic manure produced by earthworms feeding on decomposable wastes, leaving nutrient-rich casts. It improves soil structure, water holding and microbial activity and is a low-cost input.

A preparation containing living microorganisms, such as Rhizobium or Azotobacter, that fixes atmospheric nitrogen or solubilizes phosphorus when applied to seed, soil or roots, reducing chemical fertilizer need.

Combining crops with livestock, poultry, fish or other enterprises on one farm so that the waste of one component becomes input for another, raising income and spreading risk.

A fertilizer dose calculated from laboratory analysis of the field's soil, the nutrient requirement of the chosen crop and the nutrients already available, so that fertilizer is not over- or under-applied.