Potato Root Exudation and Release of Spongospora subterranea Resting Spore Germination Stimulants are Affected by Plant and Environmental Conditions

Variation in plant and environmental conditions were studied to determine the effect thereof on the exudation of low‐molecular‐weight organic compounds by potato roots. The results of the phytochemical analyses showed that among the conditions investigated, root vigour, potato cultivar, nutrients in incubation solution and temperature influenced the number and the type of primary metabolites released. Moreover, these conditions influenced our detection of compounds known to stimulate germination of resting spores of the pathogen Spongospora subterranea, causal agent of powdery scab and root diseases of potato. We conclude that changes in plant and environmental conditions can affect the release of specific compounds that stimulate germination of S. subterranea resting spores. The impact of the factors affecting potato root exudation on subsequent disease development is discussed.