Low cost multipurpose greenhouse (MGH)

It is possible to cultivate any crops in any region of the world, provided that the greenhouse is properly designed and equipped to control the climatic parameters. The crop cultivated in the protected structure affects its economic viability. The two basic approaches followed in greenhouse cultivation are (i) choose a species for its high economic potential and develop the most suitable protection, growing systems and technology (ii) choose a crop suitable for existing structures within the farm and capitalize on those.
The greenhouse technology is well established for the cultivation of vegetables, flowers, and nursery growing but the construction cost of a natural ventilated greenhouse is a major hindrance in its adoption by farmers. The availability of bamboo is abundant in Jharkhand which can be utilized for construction of low cost protected structure. So there is a need for low-cost natural ventilated GH which can be used by farmers. The low-cost natural ventilated GH is a simple structure constructed with locally available materials such as bamboo, timber, etc. and UV stabilized plastic film & insect net proof material is used as cladding materials. Unlike conventional or hi-tech greenhouses, no specific control devices for regulating environmental parameters inside the greenhouse are provided.
The GH can be used successfully for round the year cultivation of tomato and capsicum by providing desirable environmental conditions. The study was conducted to find out its suitability of low-cost natural ventilated GH for round the year cultivation of tomato and capsicum. But the major challenge occurred during the summer season when air temperature and light intensity was very high. In the Jharkhand conditions ambient temperatures in summer generally exceed 330C, so evaporative cooling is the most efficient means of GH cooling, which can lower the GH temperature below the ambient air temperature but it cannot be used in low-cost natural ventilated GH. The option available for cooling the low-cost GH is natural ventilation and shading/reflection screen but the temperature inside the GH could not be reduced or maintained even up to open field temperature using the above options. The shading/reflection screen used for reducing the temperature also reduced the light intensity below the required level for the cultivation of tomato/capsicum because light passes through cladding material (UV stabilized film) and shading/reflection screen.
The low-cost MGH was constructed by using bamboo and cladding material of UV stabilized plastic film (200 microns) and the side height of the structure is covered by insect net proof material (40 mesh) accompanied by the plastic film which can be used to regulate temperature and relative humidity as per requirement. The construction cost of low-cost MGH was around Rs.288/m2 but the construction cost of a naturally ventilated tubular GH structure is Rs. 1060/m2 (up to the area of 500 m2) and for fan & pad type GH structure is Rs. 1650/m2 (up to an area of 500 m2).
Drying is a method of food preservation which reduces the moisture content of food to enhance its shelf life by preventing bacterial growth. Soil solarization is a simple, safe, and effective alternative to the toxic, costly pesticides and the lengthy crop rotations required to control damaging soil pests.
The developed low-cost natural ventilated greenhouse can be efficiently used for cultivation of tomato/capsicum and or nursery growing during the rainy & winter season but during the summer season, it can be used for solar drying and or soil solarization. Hence the developed low-cost natural ventilated greenhouse apart from cultivation and or nursery growing can be utilized for solar drying and or soil solarization, it can be called a low-cost multipurpose greenhouse (MGH).