PSI Bulletin: May 2025
Adrian Cunnington- May 26
- 8 min read
No. 05/25 SUBSCRIBER EDITION
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Dear Subscriber,
This is your May edition of our Synopsis bulletin. Apologies for its slightly late arrival this month (and, in advance for June) due to various commitments; we should be back on track by July.
The main activity for PSI recently has centred around the Strategic Potato Storage Day which ran on 21st May. Read more below in our Technical Insight section.
In the last couple of weeks, PSI has also announced that it will be running some more potato store management training this autumn. It will be a one day course to be held on Tuesday 2nd September at the Greetham Valley Hotel & Leisure Complex in Rutland, LE15 7SN. The course is limited to 16 delegates. Lunch is included and BASIS CPD points will be available.
The cost is £375 + VAT per person. At present, there is an early bird discount of £30 available to those booking before 1 July.
The first places are already being booked up, so please get in touch if you need further details and a booking form. Call 07970 072260 or email admin@potatostorageinsight.com
Best practice
Several stores are reported to still be loaded as prices start to ease down in response to new crop becoming available. In these circumstances, it is important to keep a regular check on quality and to try to maintain marketing flexibility through judicious selection of late sprout suppressant treatments, for example.
Another factor that needs to kept abreast of in long-term stored crops is the risk of senescence with some reports of significant deterioration coming through in recently-unloaded crops. Senscence results from tubers becoming overly-mature to such an extent that the physiological structure of the potato begins to break down causing discolouration of the flesh and, when fried, irreversible darkening.
Here is an adapted summary from work carried out at University of Greenwich and Sutton Bridge CSR taken from the AHDB archive. You can also download the associated research review conducted back in 2011 about senescence and, specifically, senescent sweetening.
Prolonged storage of potatoes leads to a form of sugar accumulation termed ‘senescent sweetening’ that is generally associated with a loss of cell membrane integrity within the tuber over time. Varieties differ in their susceptibility to senescent sweetening. Although the cultivars that are most susceptible to senescent sweetening tend to have short dormancy there are important exceptions to this rule such as Maris Piper and Pentland Dell.
Growth and storage conditions affect timing of sweetening: early planting, stress and warm storage temperatures - as we have experienced in recent harvests - all speed up its onset. The most widely accepted explanation for senescence is that breakdown of cellular function occurs and that this is responsible for not only sweetening but also tissue blackening, akin to bruise development, in mature tubers. Damage at the cellular level, especially membrane damage, facilitates enzyme access to starch granules thereby speeding up starch breakdown resulting in senescent sweetening. Physiological ageing of tubers is associated with increasing oxidative damage. The process of oxidative damage, and how tissues may protect themselves against it, is considered in some detail given its importance in the process of cell senescence. Strategies to assess physiological age and hence storage quality at harvest and during storage were considered.
In trials, a link between senescent sweetening and changes in the ability to protect against oxidative damage (antioxidant capacity) was established. This provides possible strategies to follow tuber damage and give an early indication of senescent sweetening. The research suggested ascorbate concentration, in particular, should be investigated as a simple indicator of changes in capacity for oxidative protection.
Technical insight
Our second grower-focused Potato Storage Day, following on from the one held in May 2024, ran successfully on Wednesday 21st May organised by Potato Storage Insight in partnership with Simon Faulkner at SDF Agriculture.
We would like to thank everyone who was involved in supporting the event in any way, be that as an exhibitor, sponsor, host or visitor on the day.
The day was very kindly sponsored by Farm Electronics and UPL and hosted by Lincolnshire Field Products at Holbeach. Geoff Hailstone from UPL welcomed visitors to the day and thanked them for supporting this initiative. He stressed the need to find ways to support the conduct, application and uptake of research, so the potato industry and storage in particular can continue to progress.
Around 120 attendees heard from:
Simon Faulkner of SDF on varieties and sprout suppression regimes
Adrian Cunnington of PSI on energy management and store assessment as a way of improving store efficiency and controlling costs.
A focus of Adrian's presentation was to identify stores' relative performance in relation to energy consumption.
He advised delegates that PSI has recently released this Electricity Usage Guide which focuses on measuring for each store's average energy consumption in kWh per tonne per day. The guide is based around figures generated from energy use surveys in real businesses over several years. By converting each store's usage to these standard units based on electricity use, stored tonnage and storage duration, it allows comparisons to be made within sectors for whatever the store's circumstances may be.
As part of his presentation, Adrian also encouraged the submission of CIPC residue data in his role as independent chair of the CIPC Residues Management Group (see feature below).
Debbie Rees of Greenwich University/NRI on crop physiology and respiration impact on weight loss & temperature control
Barbara Correia of B-Hive on remote detection of potato pathogen development using 'electronic nose' sensing.
Guy Willetts of Assimilate Systems on a new modular storage concept to optimise store airflow and control
Around 15 commercial stands also were in attendance from:
Burgess Farms | BioFresh |
Certis Belchim | CIPC Residues Monitoring Group |
Cornerstone Systems | Crop Systems |
Fireward | Frontier Agriculture |
CIPC Residues Monitoring Group | HK Timbers |
Potato Storage Insight | Omnivent |
Restrain | UPL |
Welvent |
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