Effects of soil conditions on the prevalence of netted scab

In two field trial series different planting techniques, used to alter soil conditions at planting time, and rates of seed infection with netted scab were compared regarding their effects on plant development, yield, tuber size distribution and the prevalence of netted scab in the progeny. A greenhouse pot experiment was also carried out to study the influence of soil contamination and infection of seed with the netted scab organism on the prevalence of netted scab in the progeny. Both seed infection and planting technique affected the progeny tuber infection with netted scab. Seed infection also negatively influenced plant development and yield. It is concluded that seed infection affects plant development and yield more than soil contamination does, whereas soil contamination is more an important source of progeny tuber infection.