Aphicide resistance alert in Scotland
Aphicide resistance alert in Scotland
APHICIDE failures on oilseed rape signal virus control problems for next years potato seed crops in parts of Scotland.
Aphids migrating in from burnt off potatoes multiplied rapidly in Septembers mild, dry conditions and have hammered slow-growing oilseed rape. Pyrethroid and pirimicarb sprays failed, so an emergency off-label approval for Nico Soap (nicotine) was granted on Oct 8.
That was too late to save some crops, says SAC Scottish Agronomys Huw Phillips. "In the central belt 70-80% of crops are affected to some extent and 20-30% are severely damaged."
If MACE resistance is confirmed new mode of action insecticide Plenum (pymetrozine) will need to be alternated with pirimicarb and pyrethroids to ensure control in potatoes next year. *