Several growers in the UK are looking to find new customers for potatoes in store as food service outlets across the country have closed. AHDB Potatoes warns growers that the total dose of CIPC must not exceed 24g per tonne for use in the general ware market.
The different total dose rates for Chlorpropham (CIPC) were devised by the Potato Industry CIPC Stewardship Group (PICSG) to reduce the likelihood of Maximum Residue Level (MRL) exceedances.
These decisions were based on the volatility of CIPC (which increases with storage temperature) at the highest rate, and the fact that potatoes are cut and sliced before processing.
AHDB Potatoes says that although there is freedom to move between sectors, limits are observed. Potatoes originally destined for processing are equivalent to general ware unless total CIPC dose exceeds 24 g/tonne and storage temperature is less than 5 degrees C.
Crops with a total dose greater than 24g/tonne can only be used for commercial processing.
Adrian Briddon, Crop Storage Senior Scientist at AHDB said: “Many store managers will be operating a strategy of three 12g/tonne doses of CIPC. If you’ve only applied two of your three planned doses and your store temperature is above 5oC then you can switch to general ware. As always – check with your customer first on quality, variety and assurance scheme requirements.”
The total allowable rates are:
| Market sector | Storage temperature | Total CIPC dose |
| pre-packing | less than 5C | not greater than12 g/tonne |
| general ware | greater than 5C | not greater than24 g/tonne |
| processing(includes fish and chip shop supply) | greater than 5C | 36 g/tonne |
Source: AHDB here
