Agronomist dictionary

Weather and climate

Soil drought

A condition where available soil moisture in the root zone decreases to a level that restricts or prevents normal plant growth.

Soil and tillage

Soil fertility

Soil fertility is the capacity of soil to sustain agricultural plant growth by providing essential nutrients, water, and air in adequate amounts for crop produc...

Weather and climate

Soil frost penetration depth

This is the maximum depth from the soil surface to the bottom layer where the temperature drops to or below zero degrees during the winter season.

Soil and tillage

Soil hydraulic conductivity

The ability of a soil to transmit water through its profile when subjected to surface irrigation or precipitation.

Soil and tillage

Soil microaggregates

Soil microaggregates are microscopic clusters of soil particles, typically smaller than 0.25 mm, bound together by organic matter, fungi, and minerals.

Weather and climate

Soil moisture

This is the amount of water held in the soil pores, expressed as a percentage of the dry soil mass or volume, which serves as a primary source for crop water up...

Digital farming

Soil moisture map

A spatial representation of the soil water content across a field, derived from sensor networks or satellite remote sensing data.

Soil and tillage

Soil porosity

Soil porosity is the total volume of pores and voids between soil particles, expressed as a percentage of the total soil volume.

Soil and tillage

Soil profile

A vertical section of soil from the surface down to the parent material, displaying distinct layers known as horizons.

Nutrition and fertilizers

Soil solution concentration

This is the level of mineral salts dissolved in soil moisture, which dictates the ability of plant roots to absorb water and essential nutrients.

Soil and tillage

Soil structure

Soil structure refers to the arrangement of soil particles into stable aggregates, which facilitate proper aeration, water infiltration, and root penetration fo...

Soil and tillage

Soil structure coefficient

A metric representing the ratio of water-stable soil aggregates between 0.25 and 10 mm in diameter to the total soil mass.

Soil and tillage

Soil texture

The relative proportions of soil particles of different sizes, which determines the physical and mechanical properties of the soil.

Weather and climate

Soil thermal regime

The pattern of soil temperature variations over time, determined by heat exchange processes between the soil surface, the atmosphere, and deeper soil layers.

Soil and tillage

Soil thixotropy

The property of certain moist soils to temporarily lose shear strength and transition from a solid state to a liquid-like state under mechanical stress.

Weather and climate

Soil water balance

Soil water balance is the quantitative relationship between the water inputs to the soil and the water losses over a specific period of time.

Soil and tillage

Soil water-holding capacity

Soil water-holding capacity is the ability of a soil to retain a certain amount of water within its pores against the force of gravity after excess water has dr...

Soil and tillage

Soil workability

The physical condition of the soil in which it crumbles easily under mechanical force, providing optimal conditions for cultivation and seed germination.

Machinery and irrigation

Solenoid valve

An electromechanically operated device used to automatically control the flow of water in irrigation systems via an electrical signal.

Soil and tillage

Solonetzic property

Solonetzic property refers to the presence of high levels of exchangeable sodium in the soil, which leads to poor structure and restricts water and air movement...

Sowing and varieties

Sowing

The process of placing seeds into the soil at a specific depth and spacing to facilitate germination and crop establishment.

Sowing and varieties

Sowing date

The optimal time window for planting seeds in the soil to ensure the best germination conditions and maximum yield potential for the crop.

Sowing and varieties

Sowing method

This is the system of distributing seeds within the soil, defining the row spacing and the spatial arrangement of plants to ensure optimal development.

Sowing and varieties

Sowing qualities of seeds

Sowing qualities refer to the set of physical and biological standards that determine the suitability of seeds for planting and successful germination.

Breeding and seed production

Sowing suitability

Sowing suitability is a parameter representing the percentage of seeds in a lot that are both pure and viable, calculated by multiplying seed purity by germinat...

Breeding and seed production

Species purity

Species purity is a measure of the absence of seeds of other botanical plant species within a specific seed lot.

Storage and economics

Specific air flow rate

The amount of air delivered per unit of time relative to the volume or mass of agricultural produce being processed or stored.

Storage and economics

Specific fuel consumption

This is a measure of the amount of fuel used to complete a specific unit of agricultural work, such as per hectare of tilled land or per tonne of harvested crop...

Crop protection

Spectrum of activity

The range of target pests, weeds, or pathogens that a particular pesticide is capable of controlling effectively.

Nutrition and fertilizers

Split application

A crop management practice of applying the total fertilizer requirement in several smaller doses over the growing season rather than in a single application.

Machinery and irrigation

Spray angle

The geometric angle of the spray pattern emitted by a nozzle, which determines the width of the spray coverage on the target area.

Crop protection

Spray drift

The movement of pesticide or fertilizer droplets by wind beyond the intended application area during spraying.

Machinery and irrigation

Spray drift

The physical movement of pesticide droplets through the air at the time of application to any site other than the intended area.

Crop protection

Spray solution

This is a mixture of pesticides or fertilizers with water, prepared for direct application to crops using spraying equipment.

Machinery and irrigation

Spray volume

This is the total volume of product diluted in water or another solvent applied per unit area of the treated field.

Crop protection

Spray volume rate

This is the total volume of pesticide solution applied per unit area, expressed in liters or gallons per hectare or acre.

Machinery and irrigation

Sprayer boom

A sprayer boom is a horizontal structure mounted on a sprayer that holds nozzles to evenly distribute liquid chemicals over a field crop.

Machinery and irrigation

Sprayer boom

A horizontal frame mounted on a sprayer, equipped with nozzles to distribute liquid pesticides or fertilizers evenly across the crop area.

Machinery and irrigation

Sprayer calibration

The process of adjusting a field sprayer to ensure the precise application of a specific rate of pesticides or fertilizers per unit area.

Machinery and irrigation

Sprayer section

A sprayer section is an independent part of the spray boom equipped with nozzles that can be switched on or off separately from the rest of the system.

Machinery and irrigation

Sprinkler

A sprinkler is a device used in irrigation systems to spray water over crops, simulating natural rainfall for efficient plant hydration.

Storage and economics

Starch content

The proportion of starch in a tuber (%); determines the culinary type of the variety.

Nutrition and fertilizers

Starter fertilizer

This is the application of mineral fertilizers directly into the seed furrow or rows during sowing to provide essential nutrients to young seedlings.

Growth and development

Stem elongation

A crop growth stage characterized by the rapid vertical growth of the stem and the formation of nodes above the soil surface.

Breeding and seed production

Sterility

The condition of an organism or environment characterized by the total absence of living microorganisms or the inability to reproduce sexually.

Crop protection

Stock solution

A concentrated liquid mixture of fertilizers or pesticides that is diluted with water to create a final sprayable solution for field application.

Storage and economics

Storability

The intrinsic ability of harvested fruits, vegetables, or seeds to maintain their quality, nutritional value, and marketable appearance during a specific storag...

Storage and economics

Storage moisture content

This is the amount of water present in grains or seeds that determines their stability and prevents deterioration during storage.

Storage and economics

Stored product pests

Insects and mites that infest stored grains, processed food products, and seeds in warehouses, grain elevators, and storage facilities.

Growth and development

Stress tolerance

The ability of agricultural crops to maintain productivity and viability when exposed to adverse environmental conditions.

Nutrition and fertilizers

Sulfate fertilizers

A group of mineral fertilizers providing sulfur in a plant-available sulfate form, essential for protein synthesis and plant metabolism.

Breeding and seed production

Super Elite

Super Elite seeds are high-quality planting material obtained directly from the breeder, serving as the primary stock for seed multiplication programs.

Machinery and irrigation

Surface irrigation

A method of watering crops where water is applied directly to the soil surface and spreads across the field by gravity.

Digital farming

Surface runoff and relief

This refers to the flow of rain or meltwater over soil surfaces, governed by the field's slope, topography, and the physical characteristics of the terrain.

Crop protection

Surface tension

A physical property of a liquid that determines the ability of droplets to spread across a leaf surface or remain as spheres on it.

Crop protection

Systemic action

The ability of a pesticide or fertilizer to be absorbed by a plant and translocated through its vascular system to other parts of the plant.