New measures to protect resistance
This week, the Phytophthora Taskforce presented a new potato variety scheme that should contribute to stronger resistance management in the cultivation of varieties with improved resistance to the aggressive fungal disease Phytophthora infestans.
The scheme shows which varieties are at increased risk of a resistance breakthrough if an infection occurs in another variety within the same resistance group. This is crucial, because resistance genes can be lost in the event of a breakthrough, which has undesirable consequences for the sector.
“These varieties are not immune; they can still be affected by specific Phytophthora variants,” warned agronomist Anita van Bergeijk of Agrico during a press conference in Bant, Flevoland.
Active protection and new warning app
Active protection is essential to prevent resistance loss.
Conventional growers must carry out a stop spraying in the event of an outbreak.
Organic growers must burn the crop to death to limit further spread.
An innovative measure is the development of an alert app, which warns growers when a phytophthora outbreak is detected in a variety with improved resistance. Geert Pinxterhuis, chairman of the Phytophthora Taskforce, stated that a prototype is being further developed for the coming season:
“Growers who grow varieties from the same resistance group will receive a warning to be extra alert for infestations and to intervene immediately if necessary.”
Research into resistance management: new approach from 2025
In addition to these operational measures, long-term research is also being implemented. Wageningen University & Research (WUR) is working on a public-private partnership (PPP) Resistance Management (2025-2028). This research focuses on further strengthening the Integrated Crop Management (ICM) strategy to control phytophthora more effectively.
Conventional cultivation: Experiments are being conducted with delaying the first spraying to evaluate the effect of preventive measures.
Organic cultivation: Trials will be conducted in 2025-2027 on Bionext demo fields, with neighbouring conventional cultivation fields to capture spores and improve the decision support system (BOS).
In addition, a new LiveSeq platform is being developed in collaboration with the Dutch Potato Organisation (NAO) to monitor whether potato varieties are resistant to CAA group fungicides via DNA analysis.
Сollaboration as the key to maintaining resistance
With a combination of stronger resistance management, a proactive warning system and targeted scientific research, the sector is taking important steps to minimise the damage caused by phytophthora.
How can growers best respond to these developments? What strategies do you apply to protect resistance? Share your experiences in the comments!
