Cabbage stem weevil

The Cabbage stem weevil (Neoglocianus maculaalba) is a destructive insect belonging to the Curculionidae family and the Coleoptera order. This pest is widely recognized in agronomy for its specific preference for Brassicaceae crops, often causing significant localized outbreaks in agricultural regions.

The primary hosts for this weevil include oilseed rape (canola), cabbage, mustard, and horseradish. By feeding on the internal tissues of these plants, the insect compromises the integrity of the stem, which is critical for the transportation of nutrients and water during the plant's active growth phase.

The biological cycle of this species consists of one generation per year. Adults overwinter in protected soil niches or debris, emerging in early spring as temperatures rise. Once active, they feed on young plant tissue before laying eggs within the plant stems. The emerging larvae then feed internally, causing hidden but severe structural damage.

The economic impact of the Cabbage stem weevil is observed through stunted growth, stem splitting, and vulnerability to secondary infections such as Phoma lingam. Plants damaged by the larvae often fail to produce optimal yield, leading to substantial economic losses for farmers if the infestation is not detected and treated in time.

Integrated Pest Management (IPM) is essential for controlling this weevil:

• Maintaining a crop rotation schedule that minimizes Brassicaceae density.
• Regular field scouting during early spring to determine threshold levels for chemical treatment.
• Timely application of systemic insecticides before larvae enter the stems.
• Deep plowing of fields post-harvest to reduce the overwintering population of the weevil.