Enigma V | Improving control of cabbage stem flea beetles on oil seed rape
Fera investigated combined biopesticide and insecticide approaches to manage cabbage stem flea beetle in oilseed rape. The project demonstrated restored efficacy of pyrethroids and identified practical strategies to improve pest control and crop yield.
Published on
The Challenege
Cabbage stem flea beetle (CSFB) has become a significant pest in oilseed rape (OSR) following the 2013 ban on neonicotinoid seed treatments. Control has relied heavily on pyrethroid insecticides.
Widespread use has led to resistance in CSFB populations, reducing insecticide effectiveness. Crops are most vulnerable at emergence, where feeding damage can destroy plants, and larval infestation further reduces yield.
The loss of effective control options has reduced OSR productivity and profitability, with wider implications for crop rotations and oil production. The sector required alternative approaches to manage resistance and maintain crop viability.
The Solution
Fera led the Enigma V project to investigate methods to restore the effectiveness of existing insecticides and improve CSFB control.
Laboratory studies assessed pyrethroid performance against resistant CSFB populations. These were combined with botanical oils shown to inhibit detoxification enzymes linked to metabolic resistance.
The project focused on transferring this combined approach from laboratory conditions into practical use. Glasshouse trials evaluated pyrethroids and botanical biopesticides alone and in combination.
Promising treatments were progressed to field trials, comparing untreated, pesticide-only, biopesticide-only, and combined applications. The work also included monitoring non-target invertebrates to assess environmental impact.
The Output
- Evidence of high pyrethroid resistance in CSFB populations under laboratory conditions
- Demonstration that combining botanical oils with pyrethroids increases efficacy and restores insecticide performance
- Identification of optimal pesticide and biopesticide combinations for CSFB control
- Glasshouse and field trial data on treatment effectiveness and crop damage reduction
- Assessment of non-target impacts using field monitoring methods
- Improved understanding of resistance levels within CSFB field populations
- Practical approaches to improve OSR yields through more sustainable pesticide use
