Black Gram Powdery Mildew: Erysiphe polygoni
Symptom:
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White powdery patches appear on leaves and other green parts which later become dull coloured. These patches gradually increase in size and become circular covering the lower
surface also. -
When the infection is severe, both the surfaces of the leaves are completely covered by whitish powdery growth. Severely affected parts get shrivelled and distorted.
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In severe infections, foliage becomes yellow causing premature defoliation. The disease also creates forced maturity of the infected plants which results in heavy yield losses.
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The pathogen has a wide host range and survives in the oidial form on various hosts in the off-season.
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Secondary spread is through air-borne oidia produced in the season.
Management:
- Spray NSKE 5% or Neem oil 3% twice at 10 days interval from initial disease appearance.
- Spray Eucalyptus leaf extract 10% at initiation of the disease and 10 days later.
- Do Spray Carbendazim 500 g or wettable sulphur 1500g/ha or Propiconazole 500 ml/ha at the initiation of the disease and 10 days later.
Source-
- TamilNadu Agritech Portal
