protected cultivation and types of protected cultivation
- 2. Introduction of Greenhouse Technology Greenhouse technology is the practice of using controlled environmental conditions to create an optimal growing environment for plants. It involves the use of structures, usually made of transparent materials like glass or plastic, to trap solar radiation and maintain a controlled climate. Greenhouses allow for around year cultivation of plants, protection from adverse weather conditions, and the ability to optimize growth factors such as temperature, humidity, light, and carbon dioxide levels.
- 3. Protected cultivation on commercial scale is undertaken in over 50 countries across the globe. First modern greenhouses were built in Italy in the thirteenth century. In India, green house technology started in 1980 and initially it was used for research only. In India, first polyhouse was designed and set up in 1985 at Leh (J& K). In India , Maharashtra is covered major area of green house.
- 4. Protected Cultivation: A technique wherein the microclimate around the plant is controlled fully, partially or modified to protect the crop from adverse weather. Protected cultivation ensures: Conservation of soil moisture Efficient use of energy mainly solar
- 5. Present Scenario Country ha (‘000) China 81.0 Spain 70.4 South Korea 47.0 Japan 36.0 Turkey 25.0 India 25.0 Italy 16.5
- 6. Need of Protected Cultivation Higher yield Year around cultivation Better quality Off-season production Assured production Generate self employment for the educated rural youth in the farm sector
- 7. Least pesticide residues Controlled pollination Vagaries of weather Easier plant protection Weed free cultivation
- 8. Types of GH • Classification based on GH working Principles • GH type based on cost of construction or technology • GH Type Based on Construction • GH Type Based on Covering Material • GH Type Based on Shape
- 9. Classification of GH based on working principles Passive GH Do not require mechanical energy for moving fluids for their operation. Fluids & energy move by virtue of temperature gradients established by the absorption of radiation. The GH act a collector, as the glazed area, walls and roofs are used for collecting, storing and distribution of solar energy in the GH by the natural processes of conduction, convection & radiation. It depend on architectural design to maximize solar gain in winter to reduce heating and minimize them in summer to reduce cooling.
- 10. Active GH There is an external thermal energy available either from conventional fuel or solar energy through a collector panel is fed inside the GH. These GHs use fan & pumps with the help of mechanical energy to move the working fluid in the system.
- 11. Greenhouse Passive Greenhouse Active Greenhouse Heating Cooling Heating Cooling Water Storage Rock-bed Storage North Wall Munching Phase Changing Material Movable Insulation Natural Ventilatio n Shading Warm Water Soil Storage Buried Pipes Rock Piles Forced Ventilation Evaporative Earth Air Tunnel Misting
- 12. GH type based on cost of construction or technology A. Low cost or low tech GH B. Medium cost or medium tech GH C. High cost or hi-tech GH
- 13. Structure & Glazing Environment Culture method Expected yield of tomato (kg/m2/yr) Investme nt cost (Rs./m2) Canopy Root Bamboo or Wood Single layer Passive cooling (roof and side wall vents) No heating Soil Drip irrigation with manual control Med- high wire 10 – 20 300-500 Low cost or low tech GH
- 14. Structure & Glazing Environment Culture method Expected yield of tomato (kg/m2/yr) Investmen t cost (Rs./m2) Canopy Root Steel frame Double PE film or rigid plastic Passive/A ctive cooling (vents+pa d/fan) With or without air heating Basic level of computer Soil or soiless substrate Drip irrigation Some control High wire culture Longer season Usually computer ized fertigatio n 25 – 50 500 –1500 Medium cost or medium tech GH
- 15. Structure & Glazing Environment Culture method Expected yield of tomato (kg/m2/yr) Investment cost (Rs./m2) Canopy Root Steel or Aluminu m frame Glass, polyethyle ne or Polycarbo nate Forced ventilation + evaporativ e cooling + hot water pipe heating + CO2 enrichment + shading (light) + energy Soilless substrate Drip irrigation with full automated control (EC control according to light intensity) High wire culture Fully computeri zed fertigation Recirculat ion Hydropon i cs 50 – 75 More than 1500 High cost or high tech GH
- 16. Types of Greenhouses Traditional or Glass Greenhouses: These greenhouses have transparent glass walls and roofs, providing excellent light transmission. They are often permanent structures and require a solid foundation. Plastic Film Greenhouses: These greenhouses use polyethene or other types of plastic film as the covering material. They are more affordable and easier to construct than glass greenhouses. Plastic film greenhouses are commonly used in commercial agriculture. Shade Houses: These greenhouses are designed to provide shade and protect plants from excessive sunlight. They have a shading material, typically made of woven fabric or netting, to reduce light intensity and prevent plant stress. Lean-to-Greenhouses: Lean-to-greenhouses are attached to an existing structure, such as a wall or building. They rely on the support of the main structure and have one side closed, utilizing the existing wall for insulation.
- 17. • Shade Houses: These greenhouses are designed to provide shade and protect plants from excessive sunlight. They have a shading material, typically made of woven fabric or netting, to reduce light intensity and prevent plant stress. • Lean-to-Greenhouses: Lean-to-greenhouses are attached to an existing structure, such as a wall or building. They rely on the support of the main structure and have one side closed, utilizing the existing wall for insulation. • Hydroponic Greenhouses: These greenhouses are specifically designed for hydroponic cultivation, where plants are grown in nutrient-rich water without soil. • They incorporate systems for water circulation, nutrient delivery, and plant support.
- 18. Plant Response to Greenhouse Environment • Greenhouse environments can be manipulated to provide optimal conditions for plant growth and productivity. Some key factors that influence plant response in a greenhouse include: • Temperature: Greenhouses allow control over temperature, ensuring favourable conditions for plant growth. Different plants have specific temperature requirements during various stages of growth. • Light: Greenhouses can manipulate natural sunlight and supplement it with artificial lighting to provide the necessary light intensity and duration for plant growth. Light affects plant photosynthesis, flowering, and fruiting. • Humidity: Greenhouse humidity levels can be adjusted to meet plant requirements. High humidity reduces water loss through transpiration, but excessive humidity can lead to disease development.