Pollen Beetle (Meligethes spp.)

All species of pollen beetle are fairly similar in appearance, with the adults reaching about 2.5 mm in length. They are oval, metallic greenish-black and shiny. Adult pollen beetles feed on pollen and will damage unopened buds to get at the pollen, whilst the larvae feed on young pods, causing loss of pods and "blind stalks".

Pollen beetles are generally only significant pests where crops are either backward or poorly grown. Although they invade the crop from late March, they must be present in extremely large numbers, especially in winter oilseed rape, during the green/yellow bud stage to be economically important.

This is because pods which would normally not have grown to maturity on a plant may do so, compensating for the damaged flowers from other sections of the plant which could no longer produce pods. Winter oilseed rape is usually already in flower by the time the adult pollen beetles invade the crop, and therefore unless the crop is backward or thin, can compensate fairly well to pollen beetle invasion. However, spring oilseed rape is usually in the green bud stage when the adult insects arrive, and is less able to recover, and therefore spraying might be required for spring rape with lower numbers of beetles present.

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