Sitophilus oryzae

Sitophilus oryzae

Short pest overview:

Rice weevil is a stored product pest which attacks seeds of several crops, including wheat, rice, and maize. Adult rice weevils are able to fly and can live for up to two years. Females lay 2-6 eggs per day and up to 300 over their lifetime. The female uses strong mandibles to chew a hole into a grain kernel after which she deposits a single egg within the hole, sealing it with secretions from her ovipositor. The larva develops within the grain, hollowing it out while feeding.

Geographic Distribution:

It can be found on all continents.

Life Cycle:

The adults are long-lived (several months to one year). Eggs are laid throughout most of the adult life, although 50% may be laid in the first 4-5 weeks; each female may lay up to 150 eggs. Pupation occurs after about 25 days, although development periods are extremely protracted at low temperatures. Pupation takes place within the grain; the newly developed adult chews its way out, leaving a large, characteristic emergence hole.