Could adopting the North American approach to distributing sprout suppressant CIPC in potato stores save UK growers both chemical and energy costs, without compromising quality?

Finding out is the primary aim of a new three-year British Potato Council research project.

In contrast to the UK, where growers tend to switch off all power in potato stores before fogging and rely on the volume of fog produced to distribute it through the store, North American growers use the store’s fans to distribute the chemical, says the BPC’s Adrian Briddon, who spent two weeks across the Atlantic studying applications.

A device called a frequency drive, almost unheard of in UK potato stores, is plugged into the electrics to control the speed of the fans, he says.

“It converts the electricity coming in to a different frequency allowing the speed of the fan to be controlled.”

The difference in application techniques – North American growers also typically do not use solvents in the fogging process – could partly explain why their growers usually only need to apply CIPC once during the course of a season, and use a lower amount of CIPC/t of potatoes, he says.

“It seems they make a better job of getting CIPC where it is needed.”

As a result of the study trip, the BPC, Glasgow University and two commercial partners, Stored Crop Conservation and Crop Systems are embarking on a three-year evaluation of the use of frequency drives in commercial potato stores, Mr Briddon says.

“We are also doing some smaller experiment work at Sutton Bridge looking at some of the variables involved, such as air speeds and the effect of stack height.”

The ultimate aim is to determine whether UK growers can make fewer applications or use less chemical, he says.

Frequency drives are not cheap, Mr Briddon admits.

“Installation into a store will typically cost around 5000.”

But payback for the device should be pretty quick, he suggests.

“As well as possible savings on chemical, there will also be a saving on electricity.

While the fans will be working for longer periods, the lower speeds significantly reduce electricity usage.”

mike.abram@rbi.co.uk