Work Package 5 - Mechanistic understanding of tolerance to PCN to aid breeding

Work Package Lead: John Jones (James Hutton Institute)

Tolerance is the ability of a potato variety to maintain yield in the presence of PCN. However, a tolerant variety could allow large populations of PCN to develop as the nematodes are able to multiply on the roots of tolerant potato plants. After the crop is harvested, a much larger population of cysts can be returned to the soil to attack the next susceptible crop in the rotation.

Tolerance is different to resistance (which is being explored in WP3). Our current understanding of the mechanisms of tolerance is very limited.


- To understand

1) the mechanisms that explain why some cultivars are tolerant while others are not.

2) the genetic basis for PCN tolerance so that reliable markers for this trait can be identified.

3) To develop methods that allow easier assessment of PCN tolerance.


To achieve the aims, we will:

- Look at differences in root structure and the root response to PCN infection, in tolerant and intolerant varieties.

- Examine whether the same genetic mechanisms control tolerance and determinacy (a measure of the crop’s capacity to maintain leaf production after flowering). There is thought to be a link between these two characteristics.

A better and more complete understanding of tolerance will provide growers and agronomists with useful information on how to manage crops in the presence of PCN and for breeders to develop more tolerant varieties.

For more information on WP 5, please contact:




The Barnyards field trial 2022 report - A field trial investigating the resistance and tolerance characteristics of eleven potato varieties to Globodera pallida in Scotland

August 2023

In 2022 a field trial was established which aimed to provide information on the integrated control of Globodera pallida. This report publishes the results of the field trial planted at Barnyards Farm on 02/05/2022 - a location with a moderate-high PCN population. The trial consisted of 11 potato varieties (Cara, Maris Peer, Elland, Innovator, Eurostar, Buster, Amanda, Karelia, Cinderella, Lanorma, and Tyson) with varying levels of resistance to both G. Pallida and GRostochiensis (Table 1). Replicates of each variety were treated with either Nemathorin 10G (30 kg/ha, a.i. Fosthiazate) or left untreated.