Angoumois Grain Moth (Sitotroga cerealella): The Silent Enemy in Your Grain Warehouse

In the world of agricultural pests, there are many insects capable of destroying crops — but few are as stealthy and insidious as the Angoumois Grain Moth (Sitotroga cerealella). This tiny moth can silently wreak havoc on your rice and grain stores from the inside out, often before you even realize it.

Meet the Angoumois Grain Moth

• Scientific name: Sitotroga cerealella
• Family: Gelechiidae
• Order: Lepidoptera (moths)

The adult Angoumois Grain Moth is a small night-flying insect measuring only 4–5 mm long, with a wingspan of about 12 mm. Its pale brown wings are covered in fine, narrow scales and taper to sharp points. When resting, it folds its wings flat along its body, making it nearly invisible among stored grains.

Sex differences:

• Males are slightly smaller, darker in color, and more agile than females.

A Rapid Life Cycle

This moth undergoes complete metamorphosis, finishing a full life cycle in just 25–28 days:

• Egg stage (4–6 days): Females lay clusters of about 20 eggs at a time, totaling 100–500 eggs in their lifetime. Eggs are held together with a sticky secretion.
• Larval stage (19–26 days): The larvae burrow inside the grain kernels, consuming them completely from within.
• Pupal stage (5 days): Hidden inside the grain, awaiting transformation.
• Adult stage (5–7 days): Emerge, mate quickly, and start the cycle all over again.

Preferred Food Sources

• Paddy rice (their favorite!)
• Corn
• Sorghum
• Wheat
• Other stored grains

Invisible but Serious Damage

The Angoumois Grain Moth can start infesting rice even before harvest, especially if fields are left standing too long. Once hatched, larvae eat the inside of the grain, leaving behind only a fragile shell.

Damage characteristics:

• Circular holes on the grain surface
• Hollowed-out kernels that crumble easily
• Significantly reduced grain quality, making them unsuitable for sale or consumption

Distribution and Risk

This pest is found worldwide, particularly in warm, humid regions where rice and grain storage is common. Poor storage conditions dramatically increase the risk of infestation.

Prevention and Control Strategies

Temperature Control
Apply heat or extreme cold to stop the pest’s development cycle.

Reduce Grain Moisture Before Storage
Dry grains thoroughly to lower the chances of egg-laying and larval survival.

Remove Infested Products Immediately
Prevent further spread to healthy stocks.

Fumigation
Treat raw materials or rejected lots to eliminate active infestations.

Limit Storage Duration
Avoid storing grain beyond recommended periods to reduce breeding opportunities.

Conclusion

Though tiny, the Angoumois Grain Moth can cause severe economic losses by silently destroying entire grain inventories. Proactive measures — from field to warehouse — are essential to prevent these "silent destroyers" from taking over.

Prevent today, rather than repair tomorrow — do you agree?