Cabbage stem flea beetle (CSFB) and its management in oilseed rape

A lack of effective chemical options in oilseed rape has accelerated the rise of cabbage stem flea beetle (CSFB). This beetle is now pest enemy number one in this crop, with its management resting on a rapidly developing, variable and complex set of alternative solutions.

Without effective chemical protection, CSFB has become more problematic. Critically, the pest can destroy a plant’s growing point and cause crop failure. Learn about the beetle’s life cycle and the factors that influence crop risk.

Our research has identified the key components of an integrated pest management (IPM) strategy for CSFB and used a traffic-light code to indicate the current reliability for control. Effective management relies on a combination of these components.

CSFB has developed resistance to pyrethroid insecticides to various degrees, so it is essential to target – even avoid – sprays as much as possible.

We are monitoring CSFB at several core winter oilseed rape sites across England during autumn 2024.

Manual yellow water traps will be inspected for adult beetles twice a week. Each site has a trap set on the ground and 1 metre above the ground.  Symptoms of crop invasion by larvae will also be noted. Local variations in CSFB beetle pressure will also be assessed at strategic locations around one of the core sites (in Hertfordshire/Essex).

Automated yellow water traps (MagicTrap) that catch insects and identifies and counts contents at regular intervals will also be deployed at the core sites, in addition to several commercial winter oilseed rape sites. This data will be reviewed and published at the end of the monitoring season.

The monitoring data will strengthen a long-term data set that shows how CSFB migration varies annually and regionally (in response to local conditions). The information will be used to further develop and validate a decision support system that predicts local migration.

26 September 2024

We continue to see relatively little adult movement.

So far this week, we recorded no more beetles at sites 1, 2, 5 and 7.

The latest update saw three more adults recorded in the ground traps at site 6. 

Site 4 saw one more adult recorded in the latest update (in the ground trap).

To date, site 3 has recorded the most activity, although this has slowed down significantly in recent weeks. Like site 6, the latest update saw three more adults recorded in the ground trap, with an additional adult caught in the raised trap.

We also continue to see limited larval scarring.

The latest update shows the first records of limited larval scarring at site 7 (mean of 0.04 scars per plant based on the 50 sampled).

This work is helping to reveal the differences between sites and years. Ultimately, it will help us build models that predict migration.

Spray thresholds for CSFB adults

Map indicates approximate locations.

Autumn 2024 (adults)

Cumulative number of CSFB adults in yellow water traps (core monitoring sites).

Autumn 2024 (larval scarring)

Cumulative mean number of larval scars per plant (the mean is based on 50 plants).

Autumn 2022 (adults, for a comparison)

Cumulative number of CSFB in yellow water traps (core monitoring sites).

Integrated pest management (IPM) of cabbage stem flea beetle featured at the 2021 Agronomists' Conference.