Maharashtra SSC Green House Grade key terms

The process of judging a plot for greenhouse construction by checking sunlight, wind direction, drainage, water quality, soil bearing strength, road access, power supply and distance to markets before any money is spent.

The placement of a greenhouse so that its ridge or gutter line runs to give the crop maximum useful sunlight and minimum overheating, usually east-west for winter light in low latitudes and north-south where summer heat is the main risk.

A belt of trees, hedges or artificial screens planted or erected upwind of a greenhouse to reduce wind speed, cutting heat loss and structural load; it must be permeable and placed at a distance so it does not shade the house.

The gentle slope of the land or of the greenhouse floor and surrounding field that lets rain and surplus irrigation water flow away, preventing waterlogging at the root zone and erosion around foundations.

The force that moving air exerts on the greenhouse frame and covering, calculated from local design wind speed; it decides the strength of arches, purlins and foundation anchors in cyclone-prone districts.

The weight of accumulated snow that a greenhouse roof must carry without collapse, a design value used in hilly and cold areas that sets the spacing and section of structural members.

A triangulated framework of members used to span a wide greenhouse width with less steel than a plain beam, carrying roof covering and equipment loads down to the columns.

The height of the lowest point of the roof where rainwater is collected; it governs headroom for workers, machinery and tall crops and strongly affects internal air volume and temperature buffering.

A design in which several parallel greenhouse spans share common gutters, forming a large connected block that saves heat, land and cladding cost and is common in commercial vegetable and flower production.

A greenhouse structure covered with plastic film rather than glass, widely used in Indian protected cultivation in naturally ventilated, fan-and-pad or high-tech forms depending on the level of climate control fitted.

Polyethylene or similar plastic sheeting made with additives that resist sunlight degradation, so the covering keeps its strength and light transmission for several seasons instead of turning brittle and tearing.

The share of incoming solar radiation that passes through a covering material into the crop canopy; dust, condensation, ageing and dirt films reduce it, so covers must be cleaned and replaced on schedule.

Sunlight scattered in many directions by a treated covering or screen, which spreads illumination deeper into the canopy and reduces leaf scorch and uneven growth compared with direct beam light.

A woven or knitted fabric or an external whitewash layer that cuts a chosen percentage of solar radiation to lower leaf temperature and heat load during hot months, often retractable for seasonal control.

A fine mesh fitted over ventilation openings and sides to stop insect vectors such as whitefly, thrips and aphids entering the house, while allowing enough air movement to limit heat build-up.

A structure cooled only by roof and side vents that use wind and thermal buoyancy to exchange air, without fans or cooling pads; cheap to run but limited in the temperature drop it can achieve.

An evaporative system where exhaust fans pull air through wet cellulose pads, cooling it as water evaporates; effective in dry heat but much less so in humid coastal weather.

The amount of water vapour in the air expressed as a percentage of the maximum it could hold at that temperature; too high encourages fungal disease and too low drives excessive transpiration.

The gap between the water vapour the air can hold when saturated and what it actually holds; it drives transpiration and is a better crop-control signal than relative humidity alone.

Delivery of water through narrow tubes and emitters straight to the root zone in small, frequent doses, saving water and keeping foliage dry, which lowers disease pressure inside the greenhouse.

Injecting soluble fertiliser into the irrigation stream so the crop receives water and nutrients together in controlled amounts, matched to growth stage and adjusted by measuring the electrical conductivity of the feed.

A measure of the total dissolved salts in irrigation or nutrient solution, used to check that the feed strength suits the crop and that salts are not building up in the root zone.

The proportion of applied nutrient solution that drains past the root zone on purpose to flush out accumulated salts; it is monitored to avoid both salt injury and wasteful over-irrigation.

Growing plants in a substrate or in flowing nutrient solution instead of field soil, giving the grower full control over water, nutrients and root-zone hygiene but demanding precise management.

A soilless system in which plant roots sit in or above a circulating nutrient solution, often in channels or troughs, so that water and nutrient composition can be adjusted continuously.

The solid material in which roots anchor in a soilless system, such as coco peat, rockwool, perlite or vermiculite; it must hold moisture and air while staying physically stable and free of pathogens.

A substrate made from processed coconut husk that holds water well, drains freely and is widely available in India; it must be washed and buffered to remove excess sodium and potassium before use.

A water-based mix of macro- and micro-elements prepared to a target pH and electrical conductivity for a specific crop stage, monitored and topped up as plants take up water and ions unevenly.

The volume of substrate or soil explored by roots, where moisture, air, temperature and nutrient concentration must stay in balance; most greenhouse irrigation and aeration decisions are aimed at it.

A decision framework that combines resistant varieties, hygiene, screening, scouting, biological control and, only when thresholds are crossed, selective pesticides, so that chemical use is a last resort.

Suppressing pests by releasing or conserving their natural enemies, such as predatory mites or parasitoid wasps, inside the greenhouse where insect-proof screening protects the beneficials from being lost.

Regular, structured inspection of the crop to detect pests, diseases and disorders early, usually with sticky traps and random plant checks, so that control action is taken before losses spread.

A coloured adhesive card hung among plants to catch flying insects; yellow attracts whitefly and aphids while blue attracts thrips, and counts also serve as a monitoring record.

Growing horticultural crops under a structure that modifies the growing environment, allowing off-season production, higher yields and better quality but requiring investment and skilled management.

A programmable unit that switches irrigation, fertigation, vents, fans and heating according to sensor readings or time schedules, reducing labour and making the crop environment more consistent.

Rapid removal of field heat from harvested produce, by forced air, cold water or vacuum, before storage or transport, which slows respiration and extends shelf life of greenhouse vegetables and flowers.

Sorting harvested produce into uniform classes by size, colour, shape and freedom from defects so that each lot can be packed, priced and marketed consistently and buyers get predictable quality.

The unbroken sequence of cooling, cold storage and refrigerated transport that keeps perishable produce within its optimum temperature range from farm to buyer, preserving quality and value.

Clothing and gear such as gloves, goggles, respirators and boots worn while handling pesticides, disinfectants or sharp equipment in the greenhouse, reducing exposure of skin and lungs.

The minimum time that must pass after a pesticide application before workers may enter the treated greenhouse, protecting them from inhaling or touching residues that are still active.

A government programme that shares the capital cost of approved protected-cultivation structures and equipment with the farmer, usually through a state horticulture department and linked bank credit.

A written plan for a greenhouse enterprise covering costs, crop choice, yields, prices, cash flow and repayment, required by banks and subsidy agencies before finance is sanctioned.