Cabbage seed weevil

Systematic position: The cabbage seed weevil (Ceutorhynchus rapae) belongs to the order Coleoptera and the family Curculionidae. It is a highly specialized pest that poses a consistent threat to commercial cultivation of oilseed crops across temperate regions.

Host crops: The pest primarily feeds on members of the Brassicaceae family. Its main targets are oilseed rape, mustard, radish, and kale. Furthermore, various wild cruciferous weeds act as alternative hosts, maintaining the pest population levels throughout the growing season.

Biology and life cycle: Adults hibernate in the soil or under debris. Emergence occurs in early spring when temperatures rise. Females oviposit into the petioles or stems of the host plant. The larvae feed internally, causing significant structural damage, and subsequently drop to the ground to pupate in the soil. There is typically one generation per year.

Damage and severity: Larval feeding creates tunnels within the plant tissues, disrupting nutrient transport and causing internal necrosis. Externally, the infestation is marked by swelling and twisting of the stems, which can weaken the plant architecture. In cases of high infestation density, the plant vigor significantly declines, leading to reduced seed quality and yield loss.

• Implement crop rotation to break the pest cycle and disrupt habitat.
• Utilize deep tillage techniques to bury or destroy pupating larvae.
• Monitor adult activity using yellow sticky traps during the flowering and budding stages.
• Keep field margins clear of cruciferous weeds to reduce infestation pressure.
• Apply targeted insecticides when pest populations exceed economic thresholds.