Damaged beans containing larvae are unsaleable for both the fresh and processing markets. Effective control of Bruchid beetles is essential to avoid the risk of poor returns if growers are to expand their bean crops for organic and conventional sustainable arable farming systems.
Project FV 322 looked at immediate solutions by addressing spray application and timing issues. To help reduce pesticide reliance, it also included work on the use of pheromones and other signalling chemicals for beetle monitoring to provide a reliable risk indicator and also screening of varieties for resistance.
In two field-scale trials, a significant level of control was achieved where sprays were applied at the early pod stage following two consecutive days when temperatures reached a maximum of 20 degsC. Control was also improved where angled spray nozzles enhanced crop canopy penetration.
Analysis of bean flower volatiles identified possible candidates to attract beetles in a monitoring system that showed promise in preliminary field trials. More than 600 Vicia faba breeding lines were screened for resistance and at least one showed significantly less Bruchid damage than the standard current varieties.
Damage assessments made on commercial crop samples were correlated with growing locations to produce a distribution map of the pest in the UK. Only crops in the north of England and Scotland were beetle-free.
Horticultural Development Company
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