Pest:Leaf webber

Hymenia recurvalis

The adult is a black moth. On the upper surface of the wings white wavy markings can be seen. Wing span is about 2.3 cm. Eggs are laid singly on leaves. Egg period is 3-4 days. The greenish larva with white lines web together the leaves and feeds from within, becoming full grown in about 2 weeks. Pupation takes place among the leaf webbing for about 10 days.

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Symptoms

  • Caterpillar webs together the leaves and feeds from with in skeletonizing the leaves completely.
  • The leaves become devoid of chlorophyll and dry up.
  • The leaf webbings are filled with black excreta of the caterpillars making the leaves unfit for consumption.

Procedure for Observation

Workout average number of leaf webs per plant by observing 20 plants selected at random. One leaf -mild; 2-5 moderate ; >5 severe.

ETL

  • Mere presence.

    • Control Measures

  • Collect and destroy the leaf webs along with caterpillars.
  • Adult moths are attracted to lights. As far as possible avoid use of insecticides.
  • In severe cases of leaf webber attack spray malathion 0.1 % .
  • Spray 4 % leaf extract of neem/clerodendron( For this soak 400 g of the leaf powder-leaves dried under shade and powdered- in one lit of water for 24 hours and filter through muslin cloth. Dissolve 400 g of ordinary soap shavings in 9 lit of water. Pour the soap solution to plant extract and mix thoroughly before spraying)