Pest:Rice Mealy Bug

Heterococcus rehi Pseudococcidae

This is a reddish white soft mealy bug found in colonies attached to the paddy stem covered over by the outer leaf sheath.It hardly moves about.This is a dry season pest.The pest at times cause severe damage in the Onattukara and Palakkad tracts.Numerous eggs are laid on the stem with in the leaf sheath. Up to 300 eggs are laid.Reproduction is parthenogenic.Eggs hatch with in 24 hrs.The pale yellowish white young ones are active and crawl on the surface for a while and settle themselves on plant stem. They grow feeding on the sap.White waxy fluff show out from the leaf sheath is the typical indication of the presence of pest.The young and adult have the same feeding habit.Adult females are stationary and wing less.Nymphal period lasts for 2-3 weeks.Several weeds are alternate hosts for mealy bugs.

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  • Pest 1
  • Pest 2

Symptoms

  • The damage is caused by hundreds of these bugs attaching themselves to the succulent stems and sucking plant sap.
  • Drainage of sap affects the growth and makes the plant stunted.
  • .In many cases no ear heads are produced and infested field show isolated patches of stunted and sickly looking plants.
  • When the outer sheath of infected stem is drawn apart numerous bugs in all stages are seen attached to the stem.

Procedure for Observation

Randomly mark 4 one sq.meter area per 0.4 Ha. Calculate the % of infested plants.

ETL

  • 5% damage.

    • Control Measures

  • Some times colonies of mealy bugs are found subject to the attack by natural enemies such as lady bird beetles and parasitic flies and wasps.
  • The pest is rather difficult to check if not controlled in the early stages by attending to the early attacked plants.
  • Multiplication of the pest can be considerably reduced by the destruction of Graminaceous and Cyperaceous weeds.
  • Appy of Verticilium lecanii @ 20 g/l or 5 ml/L. Dimethoate (Roger 30 EC)@ 0.05 % is effective in managing the pest