Potato farmers reminded of new dose rate limit for stored potato crops

CIPC works by interfering with cell division to inhibit sprout development
CIPC works by interfering with cell division to inhibit sprout development

Potato farmers and contractors are being reminded of a new dose rate limit for stored potato crops this season.

This change is part of the gradual annual reduction in CIPC total dose permitted, and is a core component of the CIPC stewardship process.

Chlorpropham (or CIPC) is isopropyl-N-(3-chlorophenyl) carbamate, and is widely used as an agrochemical applied to stored potatoes.

It works by interfering with cell division to inhibit sprout development.

This has been initiated by the Potato Industry CIPC Stewardship Group (PICSG), the industry steering group including companies holding the approvals for formulations, with a view to retaining access to the vital treatment.

For the 2016-17 season, the new statutory total dose rates for CIPC are as follows:

• Fresh market: 24 grams per tonne of potatoes

• At store temperature of 5°C or less, only a single application, up to 16 g/tonne, should be made, before the temperature is reduced below 7°C

• Processing market: 42 grams CIPC per tonne of potatoes

The new rates are down from the previous level of 30 g/tonne for fresh potatoes and 50 g/tonne for processing potatoes.

Proven to 'be effective'

Adrian Briddon of Sutton Bridge Crop Storage Research, hopes that these changes will maintain the status of zero exceedances observed in statutory testing in the last two years and help preserve the availability of this vital sprout suppressant.

"The new rates have been proven to be effective, so long as it’s evenly distributed and applied at the right time."

Adrian adds that this label change is expected to be the penultimate one, before the 2017 five-yearly formal review, a more significant impact will be felt when this comes into force.

"After this review, any store that requires a CIPC application must have an appropriate fan system installed to facilitate the active recirculation of air within the store."

He urges producers to plan ahead and have stores ready for this change.

Volume of chemical

"Investing in the equipment sooner rather than later will not only save you time next year, it will also reduce the volume of chemical required, therefore paying for itself within a year or two."

Adrian urges growers to carry out a BE CIPC Compliant Store Check prior to making a treatment.

This uses a ‘traffic light’ system, which will help to inform decisions on whether to apply CIPC.

"Green means it’s good to go ahead with an application, amber highlights an area of concern and red shows a problem that must be addressed before application.

"Even though the last exceedance of the MRL for CIPC, in statutory testing, was observed over two years ago, we must ensure that the industry works together and adheres to the new guidelines in order for the product to remain available on the market," concludes Adrian.