Pest:Whorl Maggot

Hydrellia philippina Ephydridae

The adult is a small dark fly first recorded in Kerala in 1970.It lays single egg on the leaf surface.Larva moves to the centre of the plant and feed on the inner margin of the developing leaves.Greenish yellow larva rests in the centre of the leaf whorl the colour of the larva is same as young leaves.Pupae are found outside the stem.Total life cycle covers 4 weeks.

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  • Pest 1
  • Pest 2
  • Pest 3
  • Pest 4
  • Pest 5
  • Pest 6
  • Pest 7

Symptoms

  • Typical damage is degenerated tissue along the inner margins of emerging leaves.
  • As the leaves expand yellow damaged areas become conspicuously visible.
  • Tillering is reduced and maturity may be delayed.
  • Whorl maggot attacks fields with standing water.Damage occurs from seedling to maximum tillering stage.

Procedure for Observation

Randomly mark 4 one meter sq.plots from 0.4 Ha.Assess the total number of hills showing symptoms from 4 meter square.Take average.

ETL

  • 2% hills showing symptoms from nursery to mid tillering stage.

    • Control Measures

  • Drain water from the field and keep it in that condition for 48 hrs.
  • If chemical spraying is warranted apply Imidacloprid Confidor 200 SL or Tatamida 200 SL 150 ml per Ha.