Warning issued over potato sprout suppressant

Farmers risk further restrictions if they apply a second CIPC treatment as a sprout suppressant to potatoes in low-temperature stores this season.
A second application risks exceeding MRL levels – threatening the future availability of CIPC products, said David Walker, chairman of the Fresh Potato Suppliers Association. The industry could not afford to have any further MRL.
A slow start to planting this spring led some people to believe they might hold on to stored crops for longer this season. But the position on planting is now more positive, with 70% of the crop now in the ground, according to Potato Council figures.
See also: campaign on the correct use of CIPC
This season had demonstrated the importance of having a clear sprout control strategy and ensuring stores were fit for purpose, said Mr Walker. “There are pressures on stores and managing crop supply is going to be challenging.”
Crops in stores that had been correctly configured had been holding well – even at dose rates below the maximum permitted on the label. But Mr Walker added: “How far in advance you can plan unloading may well determine how successful the season is.”
Mike Storey, head of research and development at the Potato Council, acknowledged that sprout regrowth had occurred in some stores. Producers should consider using ethylene or spearmint oil sprout suppressants rather than CIPC, he agreed.
Dr Storey also chairs the potato industry CIPC stewardship group – set up to promote the responsible use of CIPC sprout suppressants. There had been no MRL exceedances so far this season, but a second CIPC application would be a risk.
Nick Green, chairman of the applicators group at the National Association of Agricultural Contractors, said sprout control was most successful in stores where positive ventilation systems were used to achieve a uniform distribution of CIPC fog.
Mr Green said: “All of the CIPC members are sticking robustly with stewardship group recommendations to treat low-temperature stores only once with CIPC and they are actively helping store managers with alternative sprout control strategies.”