UK sugar beet growers gain extra insecticide for virus yellows
Sugar beet growers now have a choice of approved insecticides for controlling aphids carrying beet yellows virus following the approval of InSyst.
It is reported by Farmers Weekly.
Following the loss of Biscaya (thiacloprid), growers were down to just one authorised foliar product – Tepekki (flonicamid) – with just one application per crop.
Certis product manager Henry Welham says this would be nowhere near sufficient to keep virus out of crops in a high-risk year.
«The authorisation adds a much-needed second foliar spray to growers’ defences», — he says.
He add that it provides rapid knockdown of peach-potato aphid (Myzus persicae), which is very useful early in the season to prevent early virus build up, which has the greatest impact on yield.
The product is permitted for one application per crop.
Mr Welham adds that the label states that the rate should not be lower than specified to ensure good control and to prevent the likelihood of resistance build up.
For prevention of beet yellowing virus transmissions, the British Beet Research Organisation (BBRO) advises aphid control is only needed when they exceed the threshold of one green wingless aphid per four plants up to the 12 true leaf stage.
Then it falls to one a plant from 12 to 16 true leaves.
Mr Welham says: «InSyst has shown good persistence in trials keeping aphid numbers very well controlled for two weeks following treatment. Thereafter it’s vital to monitor numbers against thresholds and apply a further treatment of a different product if needed».
Currently the only option is flonicamid, but the BBRO continues to work to secure a third aphicide spray for use in 2022.