Urgent research to understand the nature and extent of insecticide resistance in an increasingly damaging pest of peas and beans is underway at Rothamsted Research. The work is in response to reports of failure to control the pea and bean weevil (Sitonalineatus) with pyrethroid sprays, which are a special chemical class of active ingredients found in many modern insecticides used by growers.
Dr Steve Foster,Research Scientist at the Department of Biological Chemistry and CropProtection, Rothamsted Research, has tested samples collected recently from Hertfordshire,Lincolnshire, Northamptonshire, Nottinghamshire and Warwickshire. He has found they contain adult weevils that are resistant to a representative pyrethroid when it is applied at a similar dose to that which is used in the field.
Dr Foster said: The next step is to find and understand the cause of this resistance which is likely to exist in other pyrethroid insecticides used. In the meantime, growers should be aware that treatment with these compounds against this pest may not be effective.
*The preliminary work has been carried out with funding from the UKsCentre of Excellence for Peas and Beans (PGRO), and also in part from Innovate UK and BBSRC,as part of a project in Agri-Tech Catalyst round 1 Lure-and-kill technology to manage beetle pests (Sitona lineatusand Bruchus rufimanus) of field beans and peas. The consortium is PGRO, BASF, Oecos, Exosect and Rothamsted Research.