Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
stabilized HDPE shade net is spread over the nylon mesh on the top of the net house to maintain
ambient temperatures suitable for crop growth. Provision should be made to pull polythene sheet
over the pro-trays in the event of rainfall by way of making low tunnel structure. For preparing low
tunnel structure, 3/4” HDPE pipes or bamboo stick and 400-gauge polyethylene sheet can be
used. The approximate cost for building stone pillar net house will be Rs. 80 to Rs. 100 per square
meter depending on the locality. Seedling rising can also be done in low cost greenhouse or
wooden poly houses.
Growing media for seedling trays:
1. Sterilized commercial growing media is better as the incidence of seedling diseases is
less or nil and it contain right amount of moisture in it.
2. The most common growing media used is coco peat, which is steam sterilized to
prevent nursery diseases.
3. Coco peat is a by-product of coir industry and it has high water holding capacity. It
should be well decomposed, sterilized and supplemented with major nutrient sources
before using. Basically coconut fiber powder is low in nutrients and high in lignin
content. Thus it need to be properly decomposed by adding major and micronutrients
and microorganisms.
4. Other growing media which have given good result are coco peat, vermicompost and
vermicompost: sand in equal proportions.
Method of seedling rising:
1. Fill the seedling tray with appropriate growing medium such as coco peat.
2. Make a small depression for sowing (0.5 cm) by fingertip in the center of the cell.
Alternatively, depression can be created by stacking about 10 trays one over other and
pressing the trays together.
3. Sow one seed per cell and cover by coco peat.
4. No irrigation is required before or after sowing if coco peat having 300-400 percent
moisture is used.
5. Keep about 10 trays one over the other for 3 to 6 days, depending on the crops. Cover the
entire stack of tray with polyethylene sheet. This arrangement ensures the conservation of
moisture in the seedling trays until germination and hence no irrigation is required till
seedling emergence. Care must be taken for spreading the trays when the seedling is just
emerging, otherwise seedlings will get etiolated.
6. Seeds start emerging after about 3-6 days of sowing depending upon the crops. Then the
trays are kept spread over a bed covered with polyethylene sheet.
7. The germinating trays are then irrigated lightly, daily depending upon the prevailing
weather conditions.
8. The trays are also drenched with fungicides as a precautionary measure against seedling
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