e course

PESTS OF GROUNDNUT :: Major Pests :: Thrips


3.  Thrips: Scirtothrips dorsalis (Thripidae: Thysanoptera)


Damage symptoms:
Nymphs and adults suck sap from the surface of the leaflets. This results in white patches on the upper and necrotic patches on the lower surface of the leaves. It consists of distortions of the young leaf lets and patchy areas of necrotic tissue that puncture and split as the leaflets grow. Injury is normally seen in seedlings.

 

Bionomics: Nymphs and adults dark coloured with fringed wings. Female thrips lay 40-50 eggs inside the tissues of leaves and shoot. Egg period 5 days, nymphal period 7-10 days and adult period is 25-30 days. There are several overlapping generations.   

 

Management

  1. Intercrop lab lab with groundnut 1:4 ratio.
  2. Spray methyl demeton 25 EC 500 ml or dimethoate 30 EC 500 ml/ ha