Tops Potato Centre
The Tops Potato Propagation Centre is located in Raphoe, Co. Donegal. The Centre has its own lands for potato propagation as well as glasshouses, polytunnels and a virus testing laboratory.
Pre-Basic Seed Potato Production
The main function of the centre is to produce pre-basic mini-tuber seed for participants in the Department's Seed Potato Certification Scheme. To do this the station must maintain nucleus stocks of healthy and genetically true to type samples of the potato varieties likely to be required for seed and eventually ware potato production. The centre maintains most of the potato varieties grown in the country.
Photo 1: Some of the Tops Centre's nucleus seed potato stocks growing in the field
Most countries have formal systems i.e. Seed Certification Schemes which include various production steps where a flush through system is applied to renew seed stocks. The production of pre-basic mini-tuber seed is the first step in the seed renewal process. This seed is certified as being free from potato virus diseases.
The Process of Producing Virus Free Seed
The virus free seed is produced in the laboratory from the sprouted tubers derived from the nucleus unit plots (photo 1) using meristem tissue culture and the mirco-propagation technique. Micro-propagation is a rapid multiplication technique and is now commonly used to produce healthy plant material. The small potato microplants are multiplied up in the laboratory (photo 2) by sub-dividing them into nodal cuttings each of which grows into a new microplant. Sub-division continues until the numbers required for transplanting to a polytunnel are produced (photos 3 & 4). The mini-tubers produced from the polytunnel (photo 5) are sold to specialised seed growers for further multiplication thus providing a regular supply of clean seed for entry into the Seed Potato Certification Scheme.
Photo 2: Golden Wonder Microplants growing in solid growth medium in laboratory before transfer to polytunnel
Photo 3: Recently transplanted microplants from laboratory growing in polytunnel
Photo 4: Microplants at a more advanced growing stage in polytunnel
Photo 5: Harvested pre-basic minituber seed potatoes from the microplants growing in polytunnel
Maintenance of National Potato Variety Collection
Ireland is oblidged under various international biodiversity commitments to conserve its native genetic resources for food and agriculture. Ireland's National Potato Collection, which is conserved in the Tops Centre, is one of the most important collections of native genetic resources held in the State.
Photo 6: Some of the varieties conserved in the Tops Potato Collection on display
Comprising over 400 accessions, the collection includes old and modern Irish potato varieties as well as varieties from abroad. Some of the old varieties date back to pre-famine times (e.g. Lumper, Black Potato and Skerry Champion). The wide variation of genetic diversity contained within the varieties conserved in this collection ensures a broad genetic base of potato germplasm is maintained. Such diversity will be available to assist potato plant breeders facing the unknown challenges of the future such as climate change.
To celebrate the FAO's International Year of the Potato in 2008, the Department of Agriculture, Fisheries and Food (DAFF) published "Potato Varieties of Historical Interest in Ireland " (ISBN No. 978-0-9565715-0-2) which contains a descriptive and photographic record of the main heritage varieties maintained by DAFF. Not all the varieties in the book are of Irish origin, but they were documented because they had strong associations with this country or they are unique to the Tops Potato collection. To download a copy of this book please click here Potato Varieties of Historical Interest in Ireland (pdf 2,041Kb)
Distinctness, Uniformity and Stability Testing Services
The Tops Centre is also responsible for conducting the Distinctness, Uniformity and Stability (DUS) testing on any new varieties entered for Plant Breeders' Rights and/or National Listing. All newly bred potato varieties must undergo a minimum two-year test to ensure that they are;
- Distinct from any other potato variety in common knowledge,
- Uniform in its relevant characteristics,
- Stable in its essential characteristics i.e. it must remain true to its description after repeated reproduction or propagation.
The guidelines under which these tests are conducted are very specific and are laid down by the International Union for the Protection of New Varieties of Plants (UPOV). An average of six newly bred varieties are DUS tested annually at the Tops Centre.
Virus Diagnostic Service
The Tops Centre provides a diagnostic service to the Department of Agriculture, Fisheries and Food's, Seed Certification field potato inspectorate staff for all the common potato virus diseases. This service is an important aid for field inspectors in that not all virus diseases are visually identifiable.
Potato Wart Disease
Potato wart disease caused by Synchytrium endobioticum can cause crop losses of up to 50-60%. Thankfully a lot of varieties are immune to the disease. New varieties are screened for susceptibility to potato wart disease by staff at Tops Potato Centre.
Photo 7: King Edward variety tubers showing Potato Wart Disease
For further information on the background and history of the Tops Potato Centre, along with additional information on the activities and services provided by the Potato Laboratory there, please click on the link below: