Assessment of potato varieties’ suitability for ethylene and low temperature storage

Effective sprout control is critical to the year-round supply of ware potatoes and the industry had largely become reliant on chlorpropham (CIPC) as a sprout supressant.  After its withdrawal of use (in 2020), alternative options were required. In the potato processing sector, lower temperature (c. 3-6°C) storage had historically not been used because of the adverse effect on processing quality. The project evaluated the influence of alternative sprout suppressants and cold temperature on the processing quality of crisping and frying varieties.

The first year of the trial (2019/20) was set up to begin to capture information on ethylene performance and low temperature storage (6°C) tolerance in a single piece of work, using crops held at 8°C treated with a single sprout suppressant (DMN) as a control. Variability between stocks supplied from industry was high and there were inconsistencies such as maleic hydrazide treatment to take into account.

In Year 2 a similar approach was taken but, to reduce variability, results were collected and presented from two trials, one assessing performance during ethylene treatment, the other assessing response to low temperature storage, albeit sharing a single control.

Overall, the results highlighted that in broad terms it is possible to successfully store crops for processing at i) lower temperatures (6°C) and ii) under ethylene treatment, as an alternative to CIPC. The key to either of these approaches, as part of a strategic change to store management for the sector, is to pick the correct varieties which satisfy the needs of the end market and also provide a consistent response under the alternative management strategy selected.

The trials highlighted some potential candidates for such strategies, but did not achieve consistent responses from a single variety grown at different sites or under a range of climatic conditions.