Worldwide Impact

Attending the UN seed potato standards meeting

Published online: Jan 10, 2018 Articles, Seed Potatoes Nina Zidack, Montana Seed Potato Certification Program
Viewed 696 time(s)

This column appears in the January 2018 issue of Potato Grower.

I was recently able to attend the Extended Bureau meeting of the 2017 Specialized Section of the United Nations Economic Commission for Europe (UNECE), which was held in Emmeloord, Netherlands, at the NAK (Dutch General Inspection Service). This is informally referred to as the rapporteurs’ meeting, and is held alternately with official meetings at the UN in Geneva, Switzerland. The funding for U.S. representation of seed potato agencies is provided by the Potatoes USA seed export program. 

A very informative portion of the meeting was devoted to true potato seed with a presentation by a representative of Naktuinbouw, the Netherlands Department for Variety Testing. Any new variety of potatoes must be listed in the Dutch Register of Varieties and has to meet criteria for distinctness, uniformity and stability. With an approved name, it can be granted plant breeders’ rights. It must be listed in the National List of Varieties, and it must demonstrate value for cultivation and use.

This was followed up by a tour of Bejo seeds in Warmenhuizen. Bejo has obtained breeders’ rights on its first true potato seed (TPS) variety. It is described as follows on their website: “This new potato hybrid, Oliver F1, can be cultivated directly from botanical seed and, after transplanting, produces table potatoes in one season. Oliver F1 is a slightly floury table potato with an oval shape, a beautiful smooth skin and a very good flavor.”  Bejo’s initial target market is Africa.

“The advantages of TPS are particularly important for smallholder farmers in Africa, Asia and Central America,” says Rien van Bruchem, Bejo’s TPS crop manager. “In these developing regions, long distribution times for tuber potatoes can have devastating effects on the quality of the propagation material. In contrast, the quality of TPS typically holds strong during the distribution process.” 

We were able to view demonstration plots of this new variety at Bejo seed headquarters in Warmenhuizen. As expected, the potatoes are not nearly as uniform as those grown from tubers, but overall, they appear to be of acceptable quality.

The highlight of the visit to NAK was learning about their pathogen-testing programs and touring their diagnostic labs. The Netherlands has completely replaced all post-harvest grow-outs with laboratory testing. A post-harvest test sample comes from 200 tubers, from which tests for six pathogens are conducted. Peels from the heel end of the tuber are analyzed for PVY, PVX , PVA and Pectobacterium using real-time PCR. Cores are also extracted from the heel end and are tested for Clavibacter and Ralstonia through immunofluorescence. Real-time assays have been developed for Clavibacter and Ralstonia but are not yet recognized in the EU directive.

A unique twist on their virus-testing program is that they combine their subsamples into 50 tubers for just four tests per 200 tubers. Their results indicate a “most probable infection” in each sample of 200. If a seed lot tests at zero out of four, it can be classified as “PreBasic.” If one out of four tests is positive, the most probable infection is 0.6 percent with a 0.01 to 3.2 percent confidence interval, and the lot can be classified as “Basic.” If two out of four are positive, the most probable infection is 1.4 percent with a 0.1 to 5.3 percent confidence interval and will also be classified as “Basic.” Three out of four indicates a probable infection of 2.7 percent with a 0.4 to 9.6 percent confidence interval, and the lot will be classified as “Certified.” A result of four out of four results in a rejection of that lot.

The highlight of the meeting portion of the trip was being able to report to the committee that the Spanish translation of the “UNECE Guide to Seed Potato Diseases, Pests and Defects” is near completion by Potatoes USA, and that it will be submitted to UN staff for approval of the translation. The group was excited at the prospect of having the translation available by the time of the World Potato Congress, which will be held in Cusco, Peru in May 2018. The delegate from Australia reported that his country is supporting the development of an app that can be used to access contents from the same publication, which they also hope to have available by the World Potato Congress.