Defra says it considered all the alternatives before granting permission for neonicotinoid pesticide treatments to be used on the 2022 sugar beet crop.
The emergency authorisation was granted subject to strict conditions. Defra said the treatment could only be used if the forecast incidence of virus yellows was at or above 19% of the crop according to independent modelling.
Following a relatively mild winter, that threshold was passed last month. Modelling predicted a 68% level of virus incidence, triggering permission for neonicotinoids to protect sugar beet seedlings from virus-carrying aphids.
Sugar beet crops have been severely affected by virus yellows in recent years, with 2020 yields down by a quarter on previous years. Other pesticide and organic treatments are not sufficiently effective in controlling viruses.
Defra said the strictly time limited authorisation of the neonicotinoid treatment – Syngenta’s Cruiser SB – would provide emergency protection against the virus, which could otherwise significantly impact sugar beet yields.
Using neonicotinoids remains tightly controlled. The maximum amount of treatment approved for use is 6% of the quantity of active substance applied on a range of crops in 2016 before neonicotinoids were prohibited.
Other conditions of the authorisation include a reduced application rate as well as a prohibition on any flowering crop being planted in the same field where the product has been used within 32 months of a treated sugar beet crop.
Scientists are working on alternative control methods. A Defra spokesperson said: “The decision to approve an emergency authorisation was not taken lightly and based on robust scientific assessment.
“We evaluate the risks very carefully and only grant temporary emergency authorisations for restricted pesticides in special circumstances when strict requirements are met and there are no alternatives.”