Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
production. The pH of soil should be 6.5- 7.5.
Varieties
A large number of commercially important varieties are grown in different parts of the
world. Among them, Regina, Nero, Parade, Mix, Alsmeera, Ibiza, Gold Spot, Sunset, Tara,
Lyonella, Ornella, Rosetta, Gloria, Alexias Ginna, Monique, Anneke are grown in India under
protected cultivation for export purpose.
Soil Sterilization
The soil of the polyhouse/ green house/ shadenet must be sterilized before planting so as
to minimize the damage from the microbes. The deep ploughed soil of the beds are treated with
formaldehyde (formalin) [2%] and air tightly covered with polythene sheets for 2-3 days. After the
treatment, the soil is uncovered and the soil is turned, the gate and the ventilators of the polyhouse
are open for air exchange so that the fumes of the formalin may wash off. The soil is then lightly
irrigated.
Need for Protected Cultivation
Gerbera, being a shade loving plant, needs about 50% shade for quality bloom production.
Moreover, the covered structure protects the plant from storms, winds, frosts, dews, gales and
other mischievous of the environment. It also helps maintain a constant and optimum temperature
and humidity as required by the plant during the period of growth. It provides an active protection
against disease and pests and ensures round the year production of cut blooms.
Propagation
Propagation may be achieved through seeds, cuttings or through dividing. Seed has a
short viability, if seeds fail to germinate within about 20 days it is likely the seeds will not germinate
at all. Plant grown from seeds can greatly differ from the parent plants. Basal cuttings should be
taken in summer the addition of a rooting hormone may increase the success and shorten the time
needed from cutting to potting into their own pots. Division should be taken in early spring, with
utmost care so as to minimize the damage to the plants root when dividing or transplanting. About
5-6 divisions can be prepared out of a healthy plant. The divisions are planted in the months of
July-August. Micropropagated plants of gerbera are nowadays being routinely used as the planting
material.
Time of Planting
Gerbera planting is done in two season-spring (January, February and March) and summer
(June, July and August), at the time planting it is important that the plants are not planted two
deeply. The crown of the plants should be in level with the soil or some what above it. When
planted deep fungal diseases easily occur and when planted shallow, shoots will be pulled loose
early while cropping.
Spacing
Gerberas are mainly planted on a raised bed system of one meter width. The working
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