ICAR-IARI Technician key terms

The process of bringing useful research-based information to rural people and helping them develop the knowledge, skills, and attitudes needed to improve their farming and home life.

The movement of proven research results from laboratories and stations to farmers' fields through extension workers, training, and communication channels so that recommended practices are actually adopted.

The mental process through which an individual farmer decides to use a new practice fully and regularly after learning about it, trying it, and judging its value on the farm.

The five-step mental sequence a person passes through before accepting a new idea: knowledge, persuasion, decision, implementation, and confirmation of the choice made.

The spread of a new practice through a social system over time, carried by communication among members and producing a characteristic S-shaped curve of cumulative adoption.

The five groups into which farmers are sorted by how early they accept a new practice: innovators, early adopters, early majority, late majority, and laggards.

A teaching method in which a recommended practice is carried out before farmers on a plot or machine, so they can see the method and its results directly and imitate it.

A planned gathering of farmers at a research station or a progressive farmer's field to observe crops, listen to scientists, and discuss results of trials in a practical setting.

A block of improved technology laid out on a farmer's field under the guidance of extension staff to show the gap between recommended practice and the farmer's existing practice.

The difference between the yield obtainable with the full recommended package of practices and the yield actually harvested by farmers in the same area.

The difference between the yield achieved on a demonstration plot and the average yield of the surrounding area, used to judge how much extension effort can raise production.

A toll-free telephone service where farmers put questions to agricultural graduates in local languages and receive immediate advice on crops, pests, weather, and schemes.

A single-window facility at an agricultural institution that provides farmers with technology, inputs, diagnostic services, and advice from one place instead of many offices.

A small voluntary group of rural people, usually women, who pool regular savings, lend to members, and later link with banks to take up income-generating farm and non-farm activities.

A strain that is genetically uniform and homozygous because it descends through repeated self-pollination from a single homozygous plant, so it breeds true in later generations.

A breeding procedure in self-pollinated crops in which individual plants are selected from segregating generations and their progeny are grown and recorded separately until uniform, stable lines are obtained.

The first-generation progeny of a cross between two genetically different parents, grown for its superior vigour and yield; seed saved from it does not repeat the same performance.

The greater vigour, yield, or adaptability shown by a hybrid compared with the average of its two parents, usually measured as a percentage increase over the better parent.

A condition in which a plant cannot produce viable pollen because of factors in the cytoplasm, inherited only through the female parent, and used to avoid hand emasculation in hybrid seed production.

The deliberate choice of individual plants or lines with desirable traits so that their seed is used for the next generation, gradually shifting the population toward the desired type.

The creation of new genetic variation by treating seed or other planting material with a physical agent such as gamma rays or with a chemical mutagen, then selecting useful changed plants.

The average performance of a parent line when crossed with a range of other lines, indicating how well its genes combine in hybrids generally rather than with one specific partner.

A decision-based approach that combines resistant varieties, cultural methods, biological control, and need-based pesticides to keep pest populations below damaging levels while limiting chemical use.

The pest population density at which control measures should be applied to prevent the pest from increasing to the level where the crop loss exceeds the cost of control.

The lowest pest population density that causes crop loss equal to the cost of the control measures needed, marking the point above which intervention is economically justified.

The suppression of a pest population by deliberately using its natural enemies, such as predators, parasitoids, or pathogens, rather than by chemical pesticides.

An insect that spends its immature stages feeding on or inside a single host insect, usually killing it, and behaves like a parasite in its youth and a free-living adult later.

A set of four tests used to prove that a particular microorganism causes a disease: it must be found in sick hosts, isolated in pure culture, reinoculated to cause the same symptoms, and reisolated.

A rapid local death of plant cells around an invading pathogen that restricts its spread, often appearing as small necrotic spots and typical of resistant varieties.

A chemical that is absorbed by the plant and moved within its tissues, so that pests feeding on treated plant parts take up the poison rather than being hit by spray deposit alone.

The process by which green plants use light energy to convert carbon dioxide and water into sugars, releasing oxygen, with chlorophyll acting as the light-absorbing pigment.

The loss of water as vapour from plant surfaces, mainly through stomata in the leaves, which pulls water and dissolved nutrients upward from the roots.

The amount of water remaining in a soil after excess water has drained away by gravity, usually a day or two after heavy rain or irrigation, when downward movement has nearly stopped.

The increase in dry weight of a crop per unit of ground area per unit of time, expressing how fast the whole plant community is adding biomass.

A measure of the acidity or alkalinity of soil, expressed on a scale from 0 to 14, which strongly influences nutrient availability and the choice of crops and amendments.

The principle that crop growth is limited by whichever essential factor is in shortest supply, so adding other nutrients or inputs cannot raise yield until that shortage is corrected.