Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
space between the two beds should be 50 cm. The distance between the plants and within the row
should be 30x 30 cm.
Nutrient Management
Gerbera requires plenty of organic matter and ample nutrients for proper growth and
production. Application of 10:15:20 g NPK/m 2 /month during first three months of planting starting
from third week and 15:10:30 g NPK/m 2 /month from fourth month when flowering starts. Apart
from this, spraying of micronutrients like boron, calcium, magnesium and copper @ 0.15 % (1.5
ml) once in a month is recommended to get better quality bloom.
Irrigation/ Water Management
After planting the crop should be sprinkler irrigated upto four weeks of planting and after
that drip irrigation should be practiced. Under polyhouse conditions the sprinkler/ drip irrigation
system facilitates higher production of quality cut flowers. The plant has a requirement of 500-700
ml per day.
Weed Management
Weeds cannot be avoided in the green house as well as fields. They deplete moisture and
nourishment from plants. Shortly after cuttings are established, carefully scratch the ground to
uproot the weeds when they are small. 2-3 hand weeding is required for proper growth of the
plant. First weeding should be done one month after planting. Weedicide can also be applied to
control weeds from the field.
Common Diseases and their control measure
Powdery mildew (Erysiphe cichoracearum): The infection causes white powdery coating on the
foliage. The plants should be lightly irrigated by drip irrigation system so that they can be protected
by excessive humidity. Destroy the affected plants and the leaves. This disease can be controlled
by spraying fenarimole (0.5ml /litre) or Dianocab (0.3 ml/litre).
Collar rot (Phytophthora cryptogea): The infection occurs just at the soil surface on the collar
portion of the stem. In some cases the leaves turn yellow and the entire plant wilt. The disease can
be controlled by drenching the soil in the root zone of the plants either with metalaxyl or with
contact fungicide such as captan and copper oxychloride @ 0.2 mg/l.
Root rot
Several fungi namely Phythium, Sclerotium rolfisii and Rhizoctonia solani affect the root
system of gerbera. Sterilizing the soil before planting and regular application of fungicide like
copper oxychloride @ 0.2 mg/l to soil may help in controlling the disease.
Common pests and their control measure
Leaf miner
This insect makes zig-zag mines inside the leaves which lead to yellowing to browning of
the leaves. The infected plants should be destroyed. Spray of Sypermethrin (0.5-0.75 ml/litre) or
Dichlovos (0.5-1.8 ml/litre) controls the miner.
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