OSR crops can be defoliated to remove the larvae with little impact on seed yield, provided the timing is right, according to research conducted in Australia and Canada. These findings have provided a catalyst for funding to promote more innovation in cabbage stem flea beetle (CSFB) management.
With pyrethroid resistance in CSFB becoming more widespread, a new research programme by AHDB will focus on non-chemical control options. Growers will be in a stronger position to manage the pest.
Led by ADAS, the latest research was commissioned in response to an earlier review which found a critical lack of understanding about the relationship between CSFB, its environment and winter oilseed rape (OSR).
Through a mix of innovative trials work and data analysis, the latest research will explore this complex relationship and improve integrated pest management (IPM) approaches – including those based on spray thresholds – and develop practical guidance.
Dr Steve Ellis, who leads the project at ADAS, said: “One of the biggest uncertainties has surrounded yield impacts. Data, particularly for the influence of larvae, is limited. Understanding the relationship between yield loss and pest infestation is crucial to the development of robust pest thresholds.
The use of OSR volunteers as a trap crop for CSFB will also be studied for the first time. It is known that CSFB wing muscles degenerate once they have located a plant to feed on and this makes it difficult for them to move on to another crop. So it might be possible to distract the beetle in this way, while the true crop emerges and grows through its first few critical growth stages.
Also the potential to defoliate affected crops before CSFB larvae move from the leaf petioles to the stem, where they cause the most damage, will also be studied.
Project details are available from the AHDB Cereals & Oilseeds website.
For full information on AHDB work in this area, visit cereals.ahdb.org.uk/neonics