Latest aphicide resistance monitoring report online
UK peach–potato aphid populations continue to show widespread resistance to pyrethroids and pirimicarb, according to AHDB-funded monitoring work. As part of the work, live samples of UK peach–potato aphid, taken from field and protected crops, are screened for resistance to key chemical groups by Rothamsted Research.
Screens include chemical groups where resistance has been detected – pyrethroids, carbamates (pirimicarb) and organophosphates – and chemical groups where resistance has not yet been detected (eg neonicotinoids) in the UK.
The latest findings show that strong pirimicarb resistance and pyrethroid resistance (conferred by MACE and super-kdr target site mechanisms, respectively) remain prevalent in peach–potato aphid samples.
Screening bioassays, conducted on live peach–potato aphid aphids, also found no significant resistance (that may compromise control) to a range of newer compounds belonging to several chemical classes.
Caroline Nicholls, who manages pest research at AHDB, said: “The relatively subtle changes in resistance, observed recently, do not mean we can take down our guard.
“The work has found evidence to suggest that some peach–potato aphid aphids from protected crop samples may have come from more genetically diverse, sexual populations, on imported plant material.
“The baseline bioassay data established for a range of insecticides in this work is essential, if we are to detect new resistance mechanisms coming into the UK from abroad, with neonicotinoid resistance being a key one to watch.”
The work – which receives significant funding and support from agrochemical companies, AHDB Cereals & Oilseeds, AHDB Potatoes, AHDB Horticulture, BBRO, the Chemicals Regulation Directorate – also monitors and establishes baseline bioassay insecticide sensitivity data for several other important aphid crop pests.
Information on the current resistance status for the full range of aphids monitored can be accessed via the Annual Project Report.
Changes in resistance (that could compromise field control) will be reported rapidly to the industry, via Insecticide Resistance Action Group (IRAG-UK) guidance published on its official web page cereals.ahdb.org.uk/irag
Source AHDB Cereals & Oilseeds