2. ◤
INTRODUCTION -
With Globalization of market, shrinking land
and climate change Protected cultivation of
high value crop has emerged as single
most important technology for ensuring-
HIGH PRODUCTIVITY
HIGH QUALITY
PROFITABLE RETURNS
3. ◤
What is Protected
cultivation -
It ensures conservation of soil moisture and efficient
use of solar energy. Currently In India around 25000 ha
land area is under protected cultivation.
Protected cultivation practices can be defined as
a cropping technique wherein the micro climate
surrounding the plant body is controlled partially or fully
as per the requirement of the vegetable species grown
during their period of growth.
9. Crite
◤ ria for site selection of a
polyhouse –
PH of soil - 5.5 -6.5
pH of irrigation water – 5.5-7.0
Continuous source of quality water
Good supply of Electricity
Green house should be located away from
buildings and trees.
Facility of good road transport and easy and
cheap availability of labors.
10. ◤
Ideal Location for Poly
houses in plains and hills –
Plains – North – south direction so
that longer side avoid sun scorching .
Hills – South / south-west / south-east
direction in hills for maximum use of
sunlight
11. T
◤ ype of polyhouses
–
Low cost or Naturally Ventilated
Polyhouses–
• They are constructed with locally available
material like bamboo, timber.
•Suitable during cold weather especially in
dry hilly areas.
• There is low initial investment.
13. Med
◤
ium cost or Partial Climate
controlled Polyhouses –
The structural frame is made up of
galvanized iron pipes.
Exhaust Fans are used for ventilation .
Cooling ads are used for humidifying
the air entering the polyhouses .
suitable for cultivation of vegetables in
low hills in NW Himalayas.
15. ◤
High cost or fully climate
controlled Polyhouses –
They consist of sensors .
The frame is made up of iron or Aluminium . The designs are
dome shaped or cone shaped . They are highly durable
In India coco fibres and rice husks are used as growing
media.
Fertigation and pesticides sprays are done by fogging
Machine .
17. Pla◤
stic Low
tunnels –
These are miniature form
of polyhouse.
The size of nursery bed
is 3*10*0.15 cm.
A portable low plastic
tunnel of size 3.5*
1.20*1.0 m size with
polythene sheet of 120
GSM (Galvanized tubular
structure) is put on the
nursery bed.
18. ◤
Shadenet /shade house –
The shadenet house is ideal for cultivation of vegetable
during dry period in the tropical islands
These structures are constructed using a UV stabilized
agro-shadenet (35%–70% shade) materials for creating
partial shade condition
Shade houses are most often constructed as a pole-
supported structure and covered with polypropylene
shade fabric
20. Disadvantages of
Polyhouse Technology.
High upfront and operation
expenses
1 Lack of pollination
2 Careful precaution must be
taken to eliminate any pest or
disease to make sure next crop
won’t be affected .
Advantages of Poly house
Technology
1 – 10-12% increase in yield.
2- Reliability of crop increase in green
house cultivation .
3- Expand your growing season
4- Minimize external threat to our crop .
21. Plastic
◤ Mulches –
Mulching is a practice of
covering the soil surface
around plant to improve
crop growth and
development .
Mulch Material may be
organic (leaves , straw ,
grass, etc. or ) synthetic
plastic .
22. Fe
◤
rtigation –
It refers to the application of
fertilizers , soil amendments ,
or other water soluble
products through an irrigation
system .
It help in minimizing adverse
environmental effects by
reducing leaching of fertilizer
and other chemical below
root zone.