This study was performed to determine the host range of Spongospora subterranea f. sp. subterranea on common crops and weeds in the northeastern United States. Seedlings of the plants were grown in nutrient solutions and inoculated with spore balls of S. subterranea. The roots were microscopically examined for the presence of plasmodia or zoosporangia 14 days after inoculation. The plants were then transferred to a greenhouse and grown in a soilless mix. The roots were examined for the presence of symptoms and spore balls after 4 months. Of 26 species within 10 families from monocotyledons and dicotyledons tested, 16 species were found to be susceptible to S. subterranea. Twelve species were newly recorded hosts for S. subterranea. Gall symptoms were observed on the roots of six species and spore balls were found on three species. Evidence is presented for the first time that galls and spore balls of S. subterranea might form on non-Solanaceous species. This investigation is important for the cultural management of potato powdery scab disease because there currently are no effective controls.
All Science Journal Classification (ASJC) codes
- Agronomy and Crop Science