Using slow-speed fans to distribute CIPC sprout suppressant in long-term bulk potato stores could significantly cut the amount of active ingredient required, latest trials suggest.
A Sutton Bridge experimental unit project found that just one 21ppm dose of CIPC, applied to a commercial store of Russett Burbank using fans fitted with Inverters (Variable Frequency (Speed) Drives), in October/ November maintained sprout suppression until late June/ early July, with no need for top-up treatments
“Using the inverters to slow fan speed improves the distribution of CIPC throughout the store and improves efficacy,” explained SBEU’s Adrain Cunnington.
The results were particularly relevant given the recent introduction of a maximum residue level (MRL) of 10ppm for CIPC, which increased the need to get the most out of fewer applications, he said. “Although CIPC passed European Annex I approval, it’s currently going through re-registration in the UK, which could possibly result in further controls. Best practice needs to be followed in all cases.”
Airflow
But, while the project’s findings were promising and Inverters were already being used in North America, the technology was still relatively unknown in the UK and any growers considering using them should consult a specialist first, he stressed. For example, on refrigeration systems, if airflow over the cooling coil is reduced but fridge duty is not, the coil could freeze up.
Inverters could play another role in saving energy, Mr Cunnington added. “Two fans running at 50% flow can give the same airflow as at 100%, but at less than 50% of the cost. With electricity as the major variable cost in potato storage, there are potentially significant benefits.”
He urged all growers to measure their store’s power usage, as doing so could easily save 10%.