Insect Pests of Fruits, Plantation, Medicinal & Aromatic Crops

4. Slug caterpillar-Parasa lepida Cramer. (Cochlididae: Lepidoptera)

Damage

• The caterpillar feeds on the leaves gregariously in the beginning, subsequently they disperse.
  
• It causes severe defoliation.
Bionomics

• The adult moth is stout with wing expanse of 4.0 cm and having green wings fringed with brown patches.
  
• The eggs are laid in batches of 10-15 on the under surface of leaves.
  
• The eggs are ovals flat scale- like in shape.
  
• The fecundity is on an average 167 eggs / female.
  
• The egg period is 7 days.
  
• The caterpillar is fleshy, slug-like with yellowish green body bearing a greenish blue stripe dorsally and yellowish green stripes laterally.
  
• The larval period is 5-6 weeks undergoes seven instars.
• It pupates in a hard shield - like greyish cocoon on the tree trunks for 4-5 weeks.
Management

• Set up light traps to monitor and kill the adult moths.
• Spray the crown with carbaryl 0.1 % (or) dichlorovos 0.02 % or malathion 0.05 % solution.
• In severe cases, root feeding of monocrotophos as explained earlier under leaf eating caterpillar may be taken up with safety precautions.
• Collect all the stages of pests viz., eggs on tree trunks, leaves, larvae during migration stage, pupae in soil and leaf sheath and adult moth during emergence and destruction.
• Organise mass collection campaign involving farmers, school children and college students.
• Spray dichlorovos @ 2 ml / litre using specially designed tractor mounted tall tree sprayer.
• Dust methyl parathion or Dimethoate 0.03 % / tree using power operated bellowed crane duster to reach tall trees.
• Encourage the predatory birds to pick up the larval stages.