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Rice weevil Rice weevil size

Rice Weevil (Sitophilus oryzae)

Description: Small snout beetle about 3/32” - 1/8” long; dull red-brown to black; 4 light red to yellow markings; functional wings; densely-pitted thorax; not cold tolerant.

Life cycle: Minimum 28 days

Feeding habits: Adults feed on whole and broken kernels, can also infest grain in field; larvae grow from eggs deposited inside kernels.

Signs of infestation: Live adult weevils, and damaged grain with “shot hole” appearance.

Control tips: Two-step approach.

  1. Treat all received grain with protectants to suppress insect populations.
  2. Clean and treat empty bins with a tank mix of Diacon® IGR and Centynal™ EC Insecticide and PBO-8® Synergist or with Diacon® IGR PLUS and PBO-8® Synergist; fumigate received grain (likely to be infested with weevils during the growing period, particularly corn). Monitor grain throughout storage period; aerate grain during warm weather periods of storage to help control moisture and temperature.

Product recommendations: A tank mix of Diacon® IGR, Centynal™ EC Insecticide and PBO-8® Synergist or Diacon® IGR PLUS and PBO-8® Synergist

Application tips: When treating flowing grain on belts or at transitions, 2 or more nozzles are recommended; during auger or conveyor cup application, fewer nozzles may be used; position nozzles for full coverage of grain stream; avoid spraying onto sides of auger boots. Calibrate protectant flow rate and check often to help ensure proper application. Use automated switches to turn chemical pumps on when there is grain in the system and turn off when no grain is present.