Sugar beet growers are being urged to check crops for aphids after surveys show increasing numbers of peach-potato and green wingless aphids.
The Rothamsted Insect Survey has recorded the first peach–potato aphid (Myzus persicae) catches of 2022 and BBRO has reported that green wingless aphids are increasingly being found in non-Cruiser (thiamethoxam) treated sugar beet crops.
The BBRO is advising growers to check non-Cruiser treated crops as a priority and consider spraying if above the aphid threshold of one green wingless aphid per four plants up until the 12-leaf stage.
Current foliar spray options are Certis’ insecticide InSyst (acetamiprid) or flonicamid and one application of each is permitted per crop.
Certis technical specialist Henry Welham recommends using InSyst first. “Its rapid knockdown prevents early virus build up which has the greatest impact on yield. InSyst has also shown good persistence in trials keeping aphid numbers very well controlled for two weeks following treatment.”
The application window for InSyst is BBCH 12 (first pair of leaves unfolded) to 39 (crop cover complete) but if applied between BBCH 12 and 19 (nine or more leaves unfolded), as is likely this year, Henry notes the label restriction that acetamiprid must not be applied to the same field until the second spring after application to sugar beet.
So far there have been no reports of wingless aphids on Cruiser treated crops and BBRO has reminded growers that if they need to spray, if above threshold, they must start with flonicamid, the active in insecticides Teppeki or Afinto.
The BBRO aphid-monitoring network is now active and available on BBROplus which growers can access via the BBRO website: www.bbro.co.uk