Recent Advances in Biology, Epidemiology and Host Resistance to Potato Powdery Scab

Powdery scab of potatoes ( Solanum tuberosum ) is caused by the soil‐borne protist Spongospora subterranea f. sp. subterranea (Sss). Although Sss is considered a ‘non‐standard’ plant pathogen, it poses an increasingly significant threat to potato production worldwide. Effective management strategies to control this disease are unavailable. The development of control methods is particularly challenging due to the ability of Sss to produce robust resting spores, which persist in soil for extended periods, and the limited understanding of its biology and interaction with the host. This review summarises the current knowledge on the life cycle and epidemiology of Sss and outlines the key barriers for effective control. Particular emphasis is placed on recent advances in host resistance, drawing on molecular genetics and genomic studies that reveal potential resistance in potato. Comparative insights from Plasmodiophora brassicae , a closely related protist and the causal agent of clubroot in brassicas, are also discussed to enhance understanding of host resistance mechanisms. Collectively, these insights provide a foundation for developing durable resistance and integrated management approaches to mitigate the impact of powdery scab in potato production systems.