Thrips are small insects Fig' that live in the flowers and folded leaflets of groundnut' They are pa

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Module II Economically Important Insect Pests
Virtual Academy for the Semi Arid Tropics
Lesson 5 Thrips
Thrips are small insects (Fig.) that live in the
flowers and folded leaflets of groundnut. They
are pale cream in color, and are usually hidden.
For these reasons they are not conspicuous. They
can be present at any time of the year but are
most numerous in the post-rainy season.
Enlarged Picture of a Thrip
Course on Insect Pests of Groundnut
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• Crop Damage
• Nymphs and adults suck sap from the surface of
  the leaflets initially resulting in white
  patches on the upper and necrotic patches on the
  lower surface of the leaves.
• In severe infestations, particularly in the
  winter crop (November-December sown in southern
  India), leaf distortion causes stunted plants.
• Yield reduction is not serious.

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• Crop Damage
• Thrips are more dangerous to the crop as they
  transmit peanut bud necrosis virus disease, which
  can cause widespread plant death (Fig.).

Bud necrosis affected plant
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• Management
• Farmers often apply insecticides to control
  thrips. This often results in outbreaks of more
  serious pests.
• Insecticide application does not help to reduce
  levels of bud necrosis disease.
• Grow varieties resistance to thrips like Robut
  33-1, Kadiri 3, ICGS 86031, ICGS 11, and ICGS 44
  in endemic areas to reduce the risk of thrips
  damage and bud necrosis disease.

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• Management
• If there are more than five thrips per terminal
  (folded) leaf during 30 days after emergence in
  the post rainy season, apply Dimethoate at
  200-250 mL a.i./ha. Thereafter, it is not
  necessary to use insecticides for thrips control.

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Module II Economically Important Insect Pests
Virtual Academy for the Semi Arid Tropics
The Lesson 5 on Thrips on groundnut
concludes. The next Lesson in this Module is
about white grubs on groundnut. Select Lesson 6
in Module II from Course contents
Course on Insect Pests of Groundnut