Diseases and Management of Crops under Protected Cultivation
Diseases and Management of Crops under Protected Cultivation
Diseases and Management of Crops under Protected Cultivation
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(<strong>Diseases</strong> <strong>and</strong> <strong>Management</strong> <strong>of</strong> <strong>Crops</strong> <strong>under</strong> <strong>Protected</strong> <strong>Cultivation</strong>)<br />
Site Selection <strong>and</strong> Orientation <strong>of</strong> Green / poly house<br />
• Ground slope for drainage is an important factor.<br />
• The microclimate condition.<br />
• Adequate provision should be made to divert surface water away from the polyhouse.<br />
• A polyhouse needs a dependable source <strong>of</strong> energy in the form <strong>of</strong> electricity <strong>and</strong> /or other<br />
fuel for environmental control.<br />
• An electric power distribution line adjacent to the site will reduce the investment on cable<br />
laying.<br />
• A short access to all weather public road will facilitate material h<strong>and</strong>ling to <strong>and</strong> from<br />
polyhouse.<br />
• Nearness to the market is another added advantage.<br />
• A dependable supply <strong>of</strong> good quality water is needed for a polyhouse.<br />
• Polyhouse should be located away from other buildings <strong>and</strong> trees to avoid obstruction to<br />
sunlight.<br />
• Labour availability<br />
Orientation :Two criteria<br />
• The light level in the green house should be adequate <strong>and</strong> uniform for crop growth<br />
• The prevailing wind should not adversely affect either the structure or operation <strong>of</strong> the<br />
facility<br />
Orientation : Sunlight availability <strong>and</strong> shading effect<br />
• Single span / Free St<strong>and</strong>ing Green House<br />
o East-West Orientation<br />
• Multi Span Green House<br />
o Gutter should be North-South oriented<br />
o No object taller than 3.3m should be within 9m <strong>of</strong> the greenhouse in either east,<br />
west or south direction<br />
Greenhouse Frame<br />
• The polyhouse frame is the most important component <strong>of</strong> a greenhouse system.<br />
• It provides support for glazing material <strong>and</strong> a place for fitting <strong>of</strong> environmental control<br />
equipment.<br />
• Tubular steel sections are the most preferred structural members for greenhouse frames.<br />
• Wood <strong>and</strong> aluminum are other common materials.<br />
• Wood frame have low initial cost but have high maintenance cost<br />
• Steel pipes provide required strength at a competitive price <strong>and</strong> also an assured service life<br />
<strong>of</strong> over 20 years.<br />
• Several other single <strong>and</strong> multispan polyhouse for use in various regions <strong>of</strong> India have been<br />
developed by various PFDCs.<br />
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