Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
mortality.
9. Seedling trays are watered daily, or as needed (not too wet or too dry) using a fine
sprinkling water can with rose or with hose pipe fitted to rose.
10. Do not over irrigate the trays; if done will result in the leaching of nutrients and help in
building up of diseases.
11. The media may need to be supplemented with the nutrient solution if the seedlings show
deficiency symptom. Spray application 0.3 per cent (3g/litre) of 100 percent water soluble
fertilizer (19 all with trace elements) twice (12 and 20 days after sowing).
12. Protect the trays from rainfall by covering the polyethylene sheets in the form of low tunnel.
13. Harden the seedlings by with holding irrigation and reducing the shade before transplanting
vi) Use of Nylon Net
It is important to have vegetable seedlings that are free of insect pests and disease
problems. The earlier the plants are infected with pests or diseases, the more severe the effect on
the field crop growth and yield. In this direction, growing vegetable seedling under cover using
insect proof nylon net (40-50 mesh) is a good practice. Use Casuarinas or bamboo poles or GI
pipe to support the net to be used by a small farmer. UV stabilized and properly stitched nets will
last for 6-8 years.
ii) Solarization for nursery bed sterilization:
It is a method of heating soil through sunlight by covering it with transparent polythene
sheet to control soil borne diseases including nematodes. This method used for the disinfection of
raised nursery bed made in soil to produce healthy seedlings of vegetable. Other additional
beneficial effects include control of weeds, insect pests and release of plant nutrients resulting in
increased crop growth. Solarization is a non chemical alternative for disease, insect pest and weed
control.
Methods of Vegetative Propagation:
Budding:
For budding, the thickness of the rootstock should be near to that of a pencil. It is better to
take well swollen and unsprouted buds from leaf axils of mature one-year-old twigs of the scion
variety. 'Forkert' or 'patch' methods can be used and the size of the bud wood may be nearly 2x1
cm and budded at a height of nearly 15cm above the ground level. Polythene tape can be used for
keeping the buds close to the stock, about 2 weeks after budding the tape can be opened up to
examine the success of the budding. After the bud starts sprouting the top portion can be cut.
Depending on the type of crop ‘T’ or ‘Inverted T’ budding can also be adopted for some of the
ornamental crops.
Grafting: The common method of grafting is 'inarching' or 'approach grafting'. 'Veneer' grafting
has also been found to simple and successful method. For 'Veneer' grafting the scion must be
taken from one-month-old shoot duly defoliated for forcing the buds. About 3-5 cm long shoot with
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