OSR CSFB establishment tip: Tillage techniques

Cabbage stem flea beetle (CSFB) management in oilseed rape (OSR) requires a combination of approaches. Find out how tillage techniques impact populations of the pest.

Lower disturbance establishment methods generally reduce CSFB damage in OSR.

This is due to several reasons, including:

• Better soil moisture retention, which improves crop establishment
• More straw trash, which may make it harder for CSFB to locate crops
• Less soil disturbance, because disturbed soil may attract migrating CSFB
• Improvements in habitats that support natural enemy activity, which reduces pest numbers

A five-year study consistently showed more CSFB adults and larvae in conventional tillage systems with stubble cultivation followed by ploughing, compared to conservation tillage with non-inversion rotary cultivation and zero tillage.

The lower numbers were likely due to:

• Greater straw mulch on the soil surface
• Improved seedbed conditions, including soil moisture

A study in France assessed the proportion of plants with CSFB larvae and found comparable results to the five-year study.

Once again, lower numbers of larvae were associated with shallow tillage, compared to ploughing prior to establishment.

The researchers suggested that the stubble in the less intensive cultivation approach interfered with the life cycle of CSFB.

For example, it may have supported natural enemy populations, which reduced how many eggs CSFB adults laid.

However, the results in the French study were associated with a high level of variability and the differences were not always significant.

An unreplicated UK field trial also found that lower disturbance cultivation methods resulted in higher plant counts, reduced damage from CSFB adults and a lower larval load in the autumn.

Another study found small, but statistically significant, reductions in leaf area loss associated with double rolling to establish OSR.

When used in the appropriate conditions, rolling can help:

• Retain soil moisture
• Consolidate seedbeds
• Promote establishment
• Reduce CSFB damage

Unlike cereal stubbles, cultivating OSR stubble soon after harvest may lower CSFB pressures.

This is because it can reduce the number of viable CSFB pupae in the soil and subsequent pest pressure in nearby emerging OSR crops.

Due to the complex nature of CSFB, never rely on a single strategy.

Use integrated pest management (IPM) to layer as many techniques as possible to minimise the risks.

This page covers one component of the ‘chase perfection at establishment’ strategy.

The home page also includes information on CSFB Research+, which is generating evidence to further improve strategies.

To view all our CSFB research projects, search ‘CSFB’ on our research page.