Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
hardwood bark species as a component in growing and propagating mixes.
Fertilizers
Pre plant – gypsum, dolomite limestone, and microelements
Post plant – nitrogen, phosphorus, and potassium in a slow-release fertilizer form
Seedling Production using Seedling Trays:
It is already a commercial venture to produce the seedlings of tomato, capsicum, cauliflower and
cabbage hybrids using seedling trays and protective structure. In the past, the farmers themselves
use to produce all seedlings used for transplanting. This was all right as most of them were
growing comparatively low cost open pollinated vegetable varieties. Now a days many progressive
farmers are coming forward to take up quality seedling production using seedling trays and supply
to the individual farmers. Even for fruit crops like papaya bigger sized trays can be used for raising
the seedlings. This method is mostly adopted for raising seedlings of F1 hybrids since the cost of
the seed is quite high. The vegetable seedlings are produced under protective structures such as
insect proof net houses, shade houses and low cost naturally ventilated greenhouses.
Advantages of seedling rising through seedling trays:
1. Growing in seedling trays with right growing media helps in proper germination.
2. It provides independent area for each seed to germinate and grow.
3. Seedling mortality or damping off rates are reduced by using properly sterilized growing media.
4. Uniform and healthy growth of all seedlings.
5. Easy in handling and economy in transportation.
6. The use of trays results in win-win situation – as the grower gains and saves a lot on expensive
seeds.
7. Root development is better and root damage while transplanting is nil. Thus better transplant
establishment and crop stand.
8. Uniform and early maturity.
Protected structure for raising seedling:
The seedling trays are commonly kept under nylon net house or poly house. Net house is
found to be cost effective and feasible structure to grow vegetable seedlings. Net house is
commonly built using granite stone pillars. Stone pillars of 10’ x 6’’ x 4’’ are generally used. These
stone pillars are spaced at 5m x 5m and grouted to a depth of 2feet. The stone pillars all along the
periphery of the net house should be tied to a peg stone using guy wire. The height of the structure
should be 8 feet. On top of each stone pillar used rubber tube is tied so that sharp edges of the
pillars do not damage the nylon mesh and shade net. Wire grid is provided at the top of the
structure as support for the nylon mesh. Normally farmers cover the sides with 40 mesh UV
stabilized nylon insect proof net and in the top 50% UV stabilized HDPE shade net is used to
cover the net house. It is recommended to cover the sides and top of the net house with 40 mesh
UV stabilized nylon insect proof net. During summer and hot sunny days 25 % or 35% UV
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