A new three-year AHDB-funded project using data from more than 1000 sites, which started last September, is aiming to develop an integrated pest management (IPM) strategy for cabbage stem flea beetle (CSFB) control in oilseed rape.
There will be a review of how agronomic factors affect CSFB such as drilling date, soil type, weather, seedbed quality and proximity to the last oilseed rape crop, seed rate and variety, explained ADAS entomologist Dr Steve Ellis.
Another part of the project will assess damage to plants on 75 sites over two years at the cotyledon 2-3 leaf stage. Three AHDB Recommended List trials will be assessed for adult damage and larval infestation and there will be additional variety and seed rate studies carried out. Tolerance of different varieties to the pest will also be measured, according to Dr Ellis.
Trials attempting to lure CSFB away from oilseed rape crops to an adjacent field with OSR volunteers, which emerge earlier, are also planned as are defoliation treatments which could potentially reduce numbers of CSFB larvae without damaging the crop, according to Dr Ellis.
A trial carried out at ADAS Boxworth last year showed a wide variation between oilseed rape varieties in CSFB larvae numbers/plant. Counts were done on nine varieties with the least infested variety having seven larvae/plant ranging up to the most infested variety with 30 larvae/plant.
Names of the varieties have not yet been revealed but ADAS hopes to gain permission to publish them.