Incubation of Phytophthora ramorum-infested leaf debris in soil affects survival, sporulation capacity, and subsequent risk of epidemic development within nurseries

Abstract

Soilborne inoculum (infested leaf debris which has become incorporated into the soil) may be an important contributor to the persistence of the sudden oak death pathogen Phytophthora ramorum in recurrently positive nurseries. To initiate new epidemics, soilborne inoculum must not only be able to survive over time, but also be capable of producing sporangia during times favorable to infection of plant material at the soil surface. Current research has only assessed the recovery of this pathogen after being buried in soils. Two additional aspects of the disease cycle are being investigated in a field trial at the National Ornamentals Research Site at Dominican University of California (NORS-DUC): the infection of leaf baits at the soil surface and the capacity to produce sporangia post-incubation.

Parent Publication

• Proceedings of the sudden oak death sixth science symposium

Citation

Peterson, Ebba K.; Grünwald, Niklaus J.; Parke, Jennifer L. 2017. Incubation of Phytophthora ramorum-infested leaf debris in soil affects survival, sporulation capacity, and subsequent risk of epidemic development within nurseries. In: Frankel, Susan J.; Harrell, Katharine M., tech. coords. Proceedings of the sudden oak death sixth science symposium. Gen. Tech. Rep. GTR-PSW-255. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 48.