Management and biology of minor cereal beetles
The cereal ground beetle, cereal leaf beetle and wheat shoot beetle (sometimes known as the wheat mud beetle) are minor pests of cereals.
Cereal ground beetle
Identification of the cereal ground beetle
Scientific name: Zabrus tenebrioides
Larvae burrow into soil, pulling down and eating shoots from October to May.
Adult beetles feed on cereal ears before harvest and on split grain and stubble regrowth.
Risk factors for the cereal ground beetle
The cereal ground beetle attacks crops in England, from Oxfordshire and Cambridgeshire southwards.
Damage is worst in all-cereal rotations and with minimal cultivations.
Management of the cereal ground beetle
A non-cereal break crop or early ploughing will provide good control.
Cereal leaf beetle
Identification of the cereal leaf beetle
Scientific name: Oulema melanopus
Adults are 4–5 mm long, with a red thorax and blue-green metallic wing cases.
Larvae cover themselves with a mixture of mucus and excreta.
The cereal leaf beetle can attach itself easily to clothing during crop walking.
Adults and larvae eat long, thin strips from the leaves, leaving the lower epidermis intact.
Management of cereal leaf beetle
The cereal leaf beetle is commonly seen in cereal crops, especially oats, across the country from mid-summer.
They are very rarely of economic importance and predation usually keeps the population in check.
Wheat shoot beetle
Scientific name: Helophorus nubilus
Larvae feed at the base of the shoot, causing the plant or central leaves to yellow and die.
Damage is usually seen from January to March but can be avoided by leaving an interval between ploughing grass and drilling the crop – 1 month should be sufficient under most conditions.
The wheat shoot beetle is an occasional pest of winter cereals following a grass rotation.
Minor flea beetles
Flea beetles, such as the Wessex, striped, turnip, adult beet (or mangold) and flax flea beetles, can cause damage to cereals, sugar beet and vegetable brassicas.