The turnip aphid is a small, soft bodied insect measuring up to 3 mm in length. Their bodies have an olive to greyish-green color with distinctive dark bars on the abdomen. The siphunculi, the structures located on the end of the aphid's abdomen, are relatively long and reach the end of the aphid's body. Adult aphids can be winged or wingless, whereas nymphs resemble smaller adults in appearance but always lack wings.
Turnip aphids have a tendency to gather in dense colonies that are often coated with a thin layer of wax and are commonly found around the growing tips of plants.
While several insecticides are approved for aphid control, their application should be considered only when necessary. It is important to assess the aphid population and the level of infestation before deciding to use insecticides.
The application of insecticide seed treatments can effectively postpone the establishment of aphid colonies, minimize early infestations, restrict aphid feeding, and hinder the spread of viruses.
A targeted border spray during autumn or early winter, when aphids commence their migration into crops, could potentially provide adequate control without necessitating the application of insecticides across the entire field.
Imidacloprid is an approved insecticide seed treatment for combating turnip aphids. However, there are currently no foliar sprays specifically registered for controlling this particular species.
Whenever possible, avoid using broad-spectrum "insurance" insecticides that can harm beneficial insects and disrupt natural pest control mechanisms. Instead apply insecticides only after careful monitoring and accurate identification of the aphid species present.