PSEB SS Agriculture key terms

The branch of agriculture that deals with growing field crops and managing the soil on which they grow. It combines crop science, soil management, and field practices to raise yields sustainably.

The pattern in which crops are grown on a piece of land over time, including sequence and arrangement. Common types are sole cropping, mixed cropping, intercropping, and crop rotation, each chosen for local soil and climate conditions.

Growing different crops in a planned sequence on the same field across seasons. Alternating cereals with legumes helps restore soil nitrogen, breaks pest and disease cycles, and prevents the buildup of soil-borne pathogens.

Growing two or more crops simultaneously in the same field in separate rows or strips. It spreads risk, improves use of light and water, and can raise total returns per hectare when the crops do not compete strongly.

Producing more than one crop on the same land in a single agricultural year, either in sequence or together. It increases land-use intensity and total output, especially where water and the growing season allow.

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

A plant of the pea and bean family whose roots host nitrogen-fixing bacteria in nodules. Including legumes in rotations adds nitrogen to the soil and often improves the yield of the following cereal crop.

The conversion of atmospheric nitrogen gas into forms plants can use. Biological fixation by Rhizobium bacteria in legume root nodules supplies nitrogen naturally, while industrial fixation produces nitrogen fertilizers.

A crop grown mainly to be ploughed back into the soil while still green, adding organic matter and nutrients. Leguminous green manures such as sunhemp also enrich the soil with fixed nitrogen.

The capacity of soil to supply essential nutrients in adequate amounts and available forms for healthy plant growth. It depends on nutrient reserves, organic matter, pH, and soil biological activity.

A measure of the acidity or alkalinity of soil on a scale from 0 to 14, with 7 neutral. Most crops grow best between pH 6 and 7.5, because nutrient availability and microbial activity decline outside that range.

The decaying plant and animal residues and living organisms present in soil. It improves water holding, structure, and nutrient supply, and is the main source of soil carbon and microbial energy.

An essential element that plants need in relatively large amounts, namely nitrogen, phosphorus, potassium, calcium, magnesium, and sulphur. Deficiencies of the first three most often limit crop yields.

A material applied to soil or crops to supply essential plant nutrients. Straight fertilizers contain one main nutrient, such as urea for nitrogen, while complex fertilizers supply two or more nutrients in one product.

A preparation containing living microorganisms that improve nutrient availability to crops when applied to seed, soil, or roots. Examples include Rhizobium cultures for legumes and phosphate-solubilizing bacteria.

Decomposed mixture of animal dung, urine, and bedding used as an organic manure. It supplies nutrients in small amounts but adds valuable organic matter that improves soil structure and water retention.

Organic material produced by controlled microbial decomposition of plant and animal wastes under aerobic conditions. Well-made compost is a stable, humus-rich manure that improves soil physical and biological properties.

Calcium or magnesium carbonate or oxide applied to acidic soil to raise its pH. Liming improves nutrient availability and microbial activity, but over-application can reduce the availability of micronutrients such as zinc and iron.

The artificial supply of water to crops to supplement rainfall. Methods include surface flooding, furrow, sprinkler, and drip systems, each with different water-use efficiency and capital cost.

A method that delivers water slowly and directly to the root zone through emitters on tubes. It saves water, keeps foliage dry, and allows precise application of soluble fertilizers, but requires filtration and maintenance.

Applying soluble fertilizers through an irrigation system, usually drip, so nutrients reach the root zone with water. It improves nutrient-use efficiency and allows small, frequent doses matched to crop demand.

The amount of crop produce obtained per unit of water used, measured in kilograms per hectare-millimetre or similar units. It rises with efficient irrigation methods, mulching, and improved crop varieties.

Covering the soil surface with organic or plastic material to conserve moisture, suppress weeds, and moderate soil temperature. Organic mulches also decompose to add organic matter to the soil.

A pest control strategy that combines cultural, mechanical, biological, and chemical methods, using pesticides only when pest levels justify them. It aims to keep pest populations below economic damage thresholds while limiting costs and environmental harm.

The pest population level at which control measures are needed to prevent the pest from reaching the level where crop loss exceeds control cost. Monitoring against this threshold avoids unnecessary spraying.

Using natural enemies such as predators, parasitoids, and pathogens to suppress pest populations. It is a core component of integrated pest management and reduces reliance on chemical pesticides.

A chemical or biological substance used to kill or control pests, including insects, weeds, fungi, and rodents. Correct choice, dose, and timing are essential to avoid crop damage, resistance, and residues.

A pesticide used to control or kill unwanted plants. Selective herbicides target weeds without harming the crop, while non-selective ones kill all vegetation and are used mainly on fallow land or before planting.

Any unwanted plant growing where it competes with the crop for light, water, and nutrients. Weeds also harbour pests and diseases, so timely control protects yield and quality.

The inherited ability of a pest population to survive a pesticide dose that would normally kill it. It develops when the same chemical is used repeatedly, so rotating active ingredients and modes of action is important.

Treating seeds before sowing with fungicides, insecticides, or bioagents to protect germinating seeds and seedlings from soil-borne and seed-borne problems. It gives early protection at low cost and low chemical load.

The quantity of seed sown per unit area, chosen to give the optimum plant population for a crop and sowing method. Too low a rate reduces yield; too high a rate causes crowding and lodging.

Placing seed in the soil at the proper depth, spacing, and time so that it germinates and establishes well. Method and timing strongly influence crop stand and final yield.

The number of plants of a crop per unit area, such as plants per square metre. An optimum population balances competition between plants with full use of light, water, and nutrients.

The amount of economic produce harvested per unit area, usually expressed in quintals or tonnes per hectare. It reflects the combined effect of variety, management, weather, and pest and disease pressure.

The reduction in quantity or quality of produce between harvest and consumption, caused by spoilage, pests, moisture, or poor handling. Proper drying, storage, and grading greatly reduce such losses.

Keeping harvested produce in conditions that preserve quality and prevent spoilage until sale or use. Safe storage requires clean, dry, well-ventilated structures and control of moisture, insects, and rodents.

Sorting produce into uniform categories according to size, quality, or appearance. Grading improves market value, allows fair pricing, and supports orderly marketing of agricultural produce.

The use of machines and implements, such as tractors, seed drills, and harvesters, to carry out farm operations. It reduces drudgery and labour needs and allows timely field operations on larger areas.