Green house technology

3.  The greenhouse effect is a natural process that
warms the Earth’s surface.
 When the Sun’s energy reaches the Earth’s
atmosphere, some of it is reflected back to space
and the rest is absorbed and re-radiated by
greenhouse gases.
 When the Sun’s energy reaches the Earth’s
atmosphere, some of it is reflected back to space
and the rest is absorbed and re-radiated by
greenhouse gases.

4.  Greenhouse gases include water vapour, carbon
dioxide, methane, nitrous oxide, ozone and some
artificial chemicals such as chlorofluorocarbons
(CFCs).
 The absorbed energy warms the atmosphere and
the surface of the Earth. This process maintains the
Earth’s temperature, allowing life on Earth to exist.

6.  The Energy on the earth surface comes in
form of long wave electromagnetic radiation.
 The Long wave radiation which is being
reflected would be converted into short wave
radiation.
 GHGs allow the long wave radiation to pass
from their layer but do not allow short wave
radiation to pass.
 The reflected short wave radiation is being
re-reflected towards the earth surface in the
form of infra red radiation.

7.  This waves reflect back until the full
absorption of infrared energy is done by the
atmosphere and the earth.
 Drastically this increases the global average
temperature of the earth, and this
phenomenon is known as ‘Greenhouse
effect’.

9.  Greenhouse Technology is a agrosystem
that presents important productive
advantages in comparison to open air
cultivation.
 Started in Year 1980,under scheme
plasticulture in India.
 GHT is also related with horticulture through
National Horticultural Mission (NHM).

10.  Main purpose of GHT is productivity,
portability and sustainability.
 3 aspects require for a green house
technology
a. Agricultural Engineer for construction.
b. Horticulturist/Agronomist
c. Agro meteorologist

11.  ‘Greenhouse’ is a framed structure, covered with
transparent or translucent material under which the crops
can be grown in partially or fully controlled climatic
conditions.
 It works on ‘greenhouse effect’ principle, Where the
transparent covering material acts as GHGs.
 The green house protects the plants from adverse climatic
conditions and provide an appropriate amount of light,
temperature, humidity, carbon dioxide etc. &
 It creates a microclimate surrounding the crop that helps the
crop for maximum production with quality.

13.  Maximizes productivity/unit area
 Off season crops can be grown, which fetches
high prices in market.
 Used for raising healthy nurseries.
 Protects the plants from adverse condition
 Growing crops throughout year
 Export oriented crops
 Increasing economic returns from small
areas.
 Can be used for growing Flowers.
 Growing of Indoor crops, Roof top gardening.
 Yield is 5 to 6 times higher than outdoor
cultivation.

14.  Better supervision than open field.
 Disease free and genetically modified transgenic
crops can be grown
 Efficient utilization of insect ides, pesticides
 Weed control is easier.
 Water req. of crops is limited & can be easily
controlled by micro sprinklers.
 Maintenance of stock plants, i.e. cultivation of grafted
plants, micro propagated plants.
 Can be used as hardening chamber for tissue culture
chambers.

15.  production of hybrid seeds, high value
vegetables, ornamental plants, medicinal plants,
cut flowers and fruits, which fetch more prices
in domestic as well as international markets
 Cultivation in problematic zone such as too cold
or hot weathers, damage due to heavy rain,
storms
 Exports of agricultural produce in international
market

16.  Greenhouse technology for biotechnology-
hydroponics or nutrient film, tissue culture
raising seedling
 Greenhouse for employment generation and
increases in income
 Use of greenhouse technology under the
precision farming guidelines
enhanced crop yield by 3-4 times in case of
Tomato and 4-5 times in
Capsicum in comparison to the conventional
method of farming

17.  Even if the naturally ventilated greenhouse
structure is little costly to
begin with, once there is year round market
linkages then the payback
period would be shorter for different crops grown
under it
Year round product
Disease-free and genetically superior
transplants can be produced continuously

20.  Initial cost is very High
 Maintenance cost high
 Knowledge of various factors required to
effectively control climate inside the Greenhouse