Pest: Marginal Gall thrips

Liothrips karnyi

hripidae

Thrips live in colonies with in tubular marginal galls induced by them. The thrips are <3 mm in length and black in colour. Eggs are laid within the marginal galls on the leaf surface singly. Emerging thrips passes through first and second nymphal, pre pupal and pupal instars and become adults in 13-18 days. All stages of thrips are seen in the marginal galls.

Symptoms

  • Marginal galls are produced as a result of feeding of the leaves by thrips .
  • The galled leaves are malformed, thickened, and crinkled.

Procedure for Observation

Select 10 leaves each from 20 standards selected at random and work out the percentage of damage. Less than 10 % -mild; 10-20% moderate >20% - severe.

ETL

  • 10 %

    • Control Measures

  • Spray 2 % neem oil - garlic emulsion.
  • Spray 0.05 % dimethoate.
  • Spray Verticillium lecanii @ 20 g or 5 ml/L.