The use of tolerant and resistant potato varieties against Phytophthora infestans has been identified as a notable agricultural practice in Belgium. While these varieties are already widely used in organic farming, interest is growing among conventional growers as regulations become stricter and disease resistance challenges increase.
Phytophthora infestans, the pathogen responsible for late blight, can rapidly destroy potato foliage when weather conditions are favourable. To keep the disease under control, growers typically need between 12 and 15 fungicide applications during the growing season.
Resistant and tolerant varieties offer an alternative approach. Resistant varieties contain specific resistance genes that reduce the likelihood of infection, while tolerant varieties slow disease development and limit damage. In seasons with high disease pressure, the number of fungicide applications required for resistant varieties can be reduced by around 50%. Tolerant varieties generally require a similar number of treatments, but crop damage is significantly lower.
When disease pressure is low, fungicide use can be reduced even further. This can provide important economic benefits for growers, while also reducing environmental impact and contributing to more effective long-term resistance management.
The growing adoption of resistant and tolerant potato varieties demonstrates how variety selection can support more sustainable crop protection strategies while maintaining effective control of one of the most damaging potato diseases.
