Primary insect pests

Insects considered as primary pests of stored products cause damage to stored grains by directly feeding on the grain at some point in their lifecycle. Primary pests will attack grains that are intact and stable. Whole sound grain is stable when its temperature and moisture content are below the levels needed for germination. Primary pest species often develop and reproduce very quickly when the conditions are optimal. This allows for large populations and, therefore, considerable damage to ensue within a matter of a few months.

Many species of stored product beetles feed internally in grain kernels as larvae. Rusty grain beetles, weevils, and lesser grain borer all develop initially inside the kernel. Of the moths, only the Angoumois grain moth is an internal feeder.

List of primary insect pests

The primary pests are organized alphabetically by order, family, and scientific name. Select the common name to go directly to the corresponding information about that pest.

• Larger grain borer (Prostephanus truncatus)
• Lesser grain borer (Rhyzopertha dominica)
• Bean weevil (Acanthoscelides obtectus)
• Pea weevil (Bruchus pisorum)
• Southern cowpea weevil (Callosobruchus chinensis)
• Granary weevil (Sitophilus granarius)
• Rice weevil (Sitophilus oryzae)
• Maize weevil (Sitophilus zeamais)
• Khapra beetle (Trogoderma granarium)
• Rusty grain beetle (Cryptolestes ferrugineus)
• Flat grain beetle (Cryptolestes pusillus)
• Flour mill beetle (Cryptolestes turcicus)
• Merchant grain beetle (Oryzaephilus mercator)
• Sawtoothed grain beetle (Oryzaephilus surinamensis)
• Longheaded flour beetle (Latheticus oryzae)
• Red flour beetle (Tribolium castaneum)
• Confused flour beetle (Tribolium confusum)
• Large flour beetle (Tribolium destructor)
• Cadelle (Tenebroides mauritanicus)
• Angoumois grain moth (Sitotroga cerealella)

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• Stored product beetles found in Canada
• Stored grain pests found in Canada