PSI Bulletin: May 2024
No. 5/24 SUBSCRIBER EDITION: please go to potatostorageinsight.com/subscribe to sign up as a Synopsis subscriber. Most of our bulletins are fully accessible only to our subscribers.
This is the May edition of Synopsis, your monthly potato storage update from Potato Storage Insight.
Hopefully, there has been continued progress to get the new crop planted although it is clear that some areas have found this easier than others with continued bouts of heavy rain affecting field work.
The big highlight for Potato Storage Insight this month has been our collaboration with GB Potatoes and SDF Agriculture in putting on the Strategic Potato Storage Day which was held in south Lincolnshire on Tuesday 14th May. I would like to thank everyone who was involved in the event in any way, especially our speakers and exhibitors; we were delighted to have around 100 attendees visiting the two storage sites at Winters Lane Storage, Long Sutton and a store operated by S&S Pugh in Gedney Dyke.
Despite many reports of early unloading, some crops remain in stores to supply key markets in June and July, especially for processing and the chip shop trade. Our best practice slot this time provides a reminder for those with crops still to be unloaded of the risks of internal sprouting.
Technical Insight
STRATEGIC POTATO STORAGE DAY: 14 MAY 2024
EVENT REPORT
The event was hosted by Winters Lane Storage, Long Sutton, PE12 9BE courtesy of the Winters Lane Storage grower co-operative members.
Trials included:
Storage regimes – cold temperatures & sprout suppression options
Winters Lane have been trialling the use of warmer storage temperatures for fresh markets and feel they have attained similar quality of delivered product from a regime at c. 3.4°C compared with their previous regime which was about 1°C cooler.
Maleic hydrazide uptake – results for commercial crops were presented by Simon Faulkner of SDF. The two processing crops had a notably lower MH uptake which may help to explain the poorer level of sprout control in these two stores despite the addition of ethylene and/or DMN.
Adrian Cunnington of PSI gave an overview of the ventilation systems in the Spot stores. Around 30% of the site capacity uses the Pirie Aspire lateral flow system. These stores at WLS were used this season to store the last lifted crops as these were in most need of drying. The Aspire's positive ventilation design - which drives air through the potatoes not around them - proved invaluable in the opinion of Peter Dade, the WLS store manager. He used the ventilation running 24/7 to dry out some very wet crops and successfully stored all but 17 tonnes in a 400 tonne store. Electricity consumption was high at ~120 kWh/t (blue line: graph below) but made the difference between having a crop to sell and not.
In a second store, visitors were able to view an overhead throw fridge system fitted with a curtain plenum and a reversed fridge coil. This type of system was featured in Synopsis back in February 2022 but essentially has the coil facing the rear wall of the store rather than the crop. It is only suitable for fridge-only systems but provides a wider return route for the air giving a more even lateral air distribution, reducing the risk of 'hot spots' and sprouting in the back corners of the store. The reverse coil system's energy use was around 60 kWh/t over the season (red line: graph below).
Further information: Reversing of fridge coil AHDB case study
Dr Richard Colgan of the University of Greenwich presented data from pilot trials conducted with the SCS/CHaP P-Pod system which has operated in the SPot stores this year. The device was used to monitor multiple attributes, including changes in crop respiration and weight loss in real time (below).
After a hog roast lunch at Winters Lane and a further opportunity to visit the exhibitor stands
we visited two satellite stores at Gedney Dyke courtesy of S&S Pugh.
Summary:
Two processing stores used for commercial crops destined for McCain. One store fitted with SmartStor control equipment courtesy of Crop Systems. Ethylene control by BioFresh. 1-MCP supplied by Agrofresh. DMN applied by Potato Storage Treatments.
Storage strategies:
Elland: MH + DMN + Ethylene (store 7)
Royal: MH + 1-MCP (ethylene blocker) + ethylene (store 8)
Adrian Cunnington of PSI presented data from a small trial conducted on two varieties treated with DMN under a range of adverse conditions after which they were stored at 7.5°C (below). After c. 200 days' storage, the trial did not show any significant differences between treatments other than the lack of sprout control in Sagitta which did not receive DMN. Both crops were MH treated prior to harvest.
BEST PRACTICE
We discussed the problems of ageing crops in storage last month from the perspective of managing the risk of senescent sweetening. Another potential pitfall as crops' time in storage is extended is the risk of internal sprouting and reports of this serious issue have been received again this season...
Internal sprouting
Internal sprouting is an undesirable, but fortunately not very common, defect that can affect stored potatoes where, after treatment with a sprout suppressant, a secondary sprout (or sprouts) begins to grow into the tuber flesh. If extensive the problem can cause serious losses as it cannot usually be detected until a tuber is cut open. Usually a combination of differing factors have to be present for the problem to arise.
The greatest risk is if a variety develops aggressive sprout growth whilst stored in conducive (usually warm/moist) conditions where sufficient sprout suppressant, for whatever reason, does not adequately reach the target sites of growth.
Secondary sprouting is often a key component so, with the advent of more treatment with maleic hydrazide (MH) in recent years, this can be present and the addition of reduced doses of a follow-up treatment, such as DMN, may increase the risk of internal sprouting developing especially if application is compromised.
The problem has a higher risk of occurring in years where growing conditions promote early dormancy break. Varietal characteristics are an element of the problem so some are more prone to it than others, although data are sporadic and it is difficult to draw firm conclusions on this.
The key is to earmark any crops which may be at risk and to identify any circumstances where underdosing might be a problem. This might include:
crops already badly sprouted before treatment
extensive secondary sprouting (lateral sprouts or rosettes around eyes)
dilution of suppressant due to part-filled stores or a lack of distribution due to missing boxes/short circuiting
Checking crops after treatment by cutting tubers may be prudent in high risk scenarios as it may identify any abnormal sprout growth before it writes off a crop.
CIPC RESIDUE DATA STILL URGENTLY REQUIRED
The CIPC Residue Monitoring Group has reported that it has received only about 60% of the data it needs to supply to CRD by the end of August to ensure that we can support the new CIPC temporary Maximum Residue Level (see April's Synopsis)
Here's their latest summary of the position:
DATA REQUIREMENT NOW URGENT TO MAKE SURE POTATO STORES CAN STAY IN USE
· The CIPC Residues Monitoring Group (CRMG) is a cross-industry body which has been set up by the UK potato industry to satisfy the data submission requirements of Health & Safety Executive’s Chemical Regulation Division (CRD).
· We need data on chlorpropham (CIPC) residues in potatoes held in any potato store previously treated with CIPC.
· This is required to support the new temporary Maximum Residue Level (tMRL) for CIPC of 0.35 mg/kg effective from 10 April 2024. The tMRL is monitoring residues for CIPC as it is no longer approved for use but residues remain in store.
· We currently have about 60% of the data we need to do this. We urgently require MORE DATA from CIPC residue tests carried out on crops stored since the 2023 harvest. We need that data making available by 30 June 2024 please.
If you have CIPC residue data (even if it is a zero result) from tests on your crop done in 2023/24, such as multi-residue screen carried out for Red Tractor compliance, please share it with us.
Any growers or store managers willing to supply data from crops held in stores with a CIPC history (note all data will be submitted anonymously), are asked to email adrian@potatostorageinsight.com or contact any CRMG Group member. A submission form will then be issued for you to send in with a copy of your lab result.
The Group will ensure that the data submitted meets the quantitative and qualitative standards expected by CRD to get the new tMRL through its annual review process. But if we don’t get enough data, we face the prospect of the tMRL being reduced to the limit of detection (LoD) and that would be a disaster as all stores previously treated with CIPC would be at risk of being unusable for further potato storage. Please do your bit to help!
Failure to supply test results may result in a lower MRL of 0.01 mg/kg (Limit of Quantification) being brought in. This would mean any stores which have a CIPC history can't continue to be used, so it is important to get supporting data submitted through the CRMG. Data from box stores is particularly needed.
Contact CRMG Chair Adrian Cunnington at adrian@potatostorageinsight.com or call him on 07970 072260 and he will send you the information on how to send your data in. Results which have demonstrated no residue is present are equally as valuable as any positive findings.
SNIPPET
Did you know? International Potato Day is celebrated on 30 May... Microsoft Co-pilot provided the run down below on the occasion; click the link above for the FAO's more in-depth background.
The International Day of the Potato is celebrated each year to recognize the significant global importance of this versatile crop. Here’s why:
Global Significance: The potato (Solanum tuberosum) is a crop of enormous global significance. It is regularly consumed by billions of people worldwide and plays a crucial role in achieving key Sustainable Development Goals (SDGs), such as zero hunger, sustainable agriculture, and economic growth.
Food Security and Nutrition: As the third most consumed food crop globally, potatoes contribute to food security and nutrition. They are a staple in the diets of many people and provide livelihoods and employment opportunities for both rural and urban communities.
Environmental Resilience: Potatoes are grown across diverse farming systems, from smallholders producing heirloom varieties by hand in the Andes to large commercial, mechanized farms on different continents. Their high yield and resilience have historically provided food security during shortages, including during World War II and subsequent conflicts.
Cultural and Culinary Dimensions: The potato has a rich cultural and culinary history. Originating in the Andes, it sustained the Inca civilization and was brought to Europe in the 16th century, supporting urbanization and fueling the Industrial Revolution. Its cultivation and consumption have shaped societies and cuisines worldwide.
International Year of the Potato: The International Day of Potato builds on the International Year of the Potato, which was observed in 2008. It serves as an opportunity to underscore the importance of the crop in combating hunger, poverty, and environmental threats to agri-food systems.
Celebrating Diversity: The Day celebrates the diversity of potato varieties and recognizes the roles of small-scale family farmers, especially women, in safeguarding this crop’s wide spectrum of genetic diversity.
Advocacy and Awareness: On this day, people come together to advocate for the potato, savour its multitude of varieties, and champion the farmers and growers who produce this essential crop with the earth’s well-being in mind.
So, why not celebrate the International Day of Potato by appreciating this humble tuber and its impact on our lives?!
FORTHCOMING EVENTS
If you are hosting a potato or agricultural industry event, please send details to admin@potatostorageinsight.com. Key dates with relevance to the potato sector in the coming months in the UK include:
June
Tue 18 CUPGRA Field Day 1, Cambridge
Wed 19 - Thu 20 Lincolnshire Show, Lincoln
Thu 20 - Sun 23 Royal Highland Show, Ingliston, Edinburgh
Wed 26 - Thu 27 Royal Norfolk Show, Norwich
July
Wed 17 Hutchinsons/RAA/SDF Field Trials Day, AH Worth, Holbeach
August
Thu 1 Whole Crop Marketing Trials Day, South Cave, Yorks
Tue 6 CUPGRA Field Day 2, Cambridge
Thu 8 Potatoes in Practice 2024, James Hutton Institute, Dundee
September
Wed 4 - Thu 5 Potato Days UK hosted by Dyson Farming, Nocton, Lincoln.
November
Wed 27 CropTech, NAEC, Stoneleigh
International Events
23-26 Jun WORLD POTATO CONGRESS, Adelaide, Australia
7-12 Jul EAPR 22nd TRIENNIAL CONFERENCE, Oslo, Norway
including the 1st European Wireworm Workshop
11-12 Sep POTATO EUROPE, Villers St Christophe, Picardie, France
6-8 Nov POTATO VARIETY DAYS, Emmeloord area, The Netherlands
24-26 Nov INTERPOM '24 Kortrijk, Belgium
Remember you, or a colleague, can subscribe to Synopsis at any time by going to potatostorageinsight.com and clicking on SUBSCRIBE. We can also now take payments by credit card. Call Adrian on 01406 364795 or 07970 072260 if you have any questions.
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Synopsis is published by Potato Storage Insight Ltd., 45 Main Street, Gedney Dyke, Spalding, PE12 0AJ. UK.
© Potato Storage Insight Ltd. 2024
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