Pests
Beet leaf miner: Pegomyia hyocyami
The maggots feed in the epidermal layers of the leaf by making serpentine mines
with silvery appearance. The affected leaves turn pale yellow, get distorted and
crumpled; and gradually dry and die away.
Control: Destroy fallen leaves and other plant debris after harvest.
Web worms: Hymenia
sp. or Loxostege sp.
Green caterpillars web up the leaves and live inside the knotted mass. Flowering
and pod formation is adversely affected.
Control: Removal and destruction of webbed bunches of leaves help to check further
spread of the disease.
Semilooper: Plusia spp.
The caterpillars voraciously feed on the foliage causing severe damage.
Control: Hand picking the larvae and spraying the crop with carbaryl (0.1%) controls
the pest.
Diseases
Leaf spot: Cercospora beticola
Circular spots appear on the leaf surface, which later dry up giving a shot-hole
appearance to the leaves. In case of severe infection, leaves dry and drop prematurely,
exposing crown.
Control: Removal and destruction of affected plants, crop rotation and spraying
copper oxychloride (0.3 %) control the disease effectively.
Downy mildew: Perenospora schachtti
White powdery growth appears on the lower leaf surface. The affected leaf dries
and shrivels quickly and infected flower shoots become stunted and distorted.
Control: Phytosanitary measures, crop rotation and use of resistant cultivars are
recommended. Seed treatment with thiram (2.5-3 g/kg of seed) and spraying dithane
Z-78 (0.3 %) is also effective.
Mosaic
The infected leaves show conspicuous mottling with chlorotic, zonate ring spots
on the surface, and the plants remain stunted. Aphids spread the disease.
Control: Destruction of infected plants and controlling the aphid population by
spraying malathion (2ml/litre) prevents the spread of the disease.
Curly top: Curly top virus
The infected plant parts become thickened, leathery and distorted. Infection impairs
both yield and quality of the root. This disease is transmitted by beet leafhoppers.
Control: Use of resistant varieties; eradication of susceptible weeds and volunteer
crop plants; regulating the time of planting; use of trap crops, and malathion spray
@ 2ml/litre to control leafhoppers population are recommended.
Beet yellows
Infected leaves become chlorotic, thickened, leathery and brittle. The foliage becomes
abnormally red or yellow and often dies. This disease is transmitted mainly through
aphids.
Control: Remove infected plants and weeds from the field. Controlling aphid population
reduce disease incidence.
Purple leaf of beetroot:
Tobacco mosaic virus (TMV).
Plants become stunted and leaves show a tendency to stand erect and come closer.
Leaves of infected plants show an unusual intense purple colouration.
Control: Removal and destruction of virus-infected plants and weed hosts helps in
minimizing disease.
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