sf: we need more images of most of the beetles listet.
Storage pests: The lesser grain borer (Rhyzopertha dominica) and the khapra beetle (Trogoderma granarium)
Grains of pearl millet are attacked by major pests such as the lesser grain borer and the khapra beetle. For this reason, the popular concept that millets are hardly susceptible to damage by storage insect pests is erroneous, except for the very small-grained millets such as tef and fonio. The lesser grain borer and the kapra beetle are relatively well adapted to extremely dry conditions and will cause serious damage to millet. Other secondary storage pests do not thrive in semi-arid climates where millets are grown, where stored grain is typically very dry.
Other non-insect pests such as rats and birds may destroy a considerable part of the harvest.
- Keep millet in sealed storage e.g. in drums or underground storage. Lower the temperature during drying of millet. The optimum reproduction temperature for these pests is 30-35°C, thus lowering the temperature to around 21 degC could check reproduction (Kajuna).
- Following are some farmer's practices to manage millet storage pests in the Sahel (see reference: Sankung Sagnia):
- Hang millet heads over kitchen fires to repel storage pests with the smoke.
- Store millet on the head. This reduces damage by pests as opposed to storing it in the form of threshed grains because the glumes on the in-threshed head act as protective devices
- Mix seeds with inert substances such as sand and wood ash. These substances fill the enclosed spaces and thus prevent movement and dispersal of insects inside the stored seeds. They also act abrasive to enhance water loss through the insect cuticle, thus killing the insect.
- Mix seeds with plant materials such as leaves of Boscia senegalensis, and mint, Hyptis spp, and pulverised pepper. These materials show a repellent action against storage pests.
