Survival of three quarantine pathogens in a simulated aquatic system at different levels of pH.

Author , , ,
Date 2011.
Publication Phytopathology 101:S93.
Key Words
AbstractPhytophthora ramorum, P. alni and P. kernoviae present significant threats to plant biosecurity. As water molds, these pathogens may spread through natural waterways and irrigation systems as exemplified by P. ramorum detection in streams and ornamental nursery effluents. However, the knowledge of their aquatic biology is scarce. Here we investigated the survival of these three quarantine pathogens in response to different levels of pH in a simulated aquatic system. Experiments were conducted using 10% Hoagland’s solution as a base medium. Treatments included a pH range from 3 to 11 and exposure times from a few seconds to 14 days. After overnight exposure, the highest recovery of P. ramorum, P. alni and P. kernoviae was zero, 6.9% and 12.2%, respectively. Zoospores of P. alni survived at low rates over 14 days across all pH levels. Similar results were obtained for P. kernoviae at pH 3 to 9. Although P. ramorum zoospores failed to survive in the system, its sporangia were tolerant to all pH levels tested, and 18–43%, except for 5.9% at pH 3, survived over 14 days. Additional experiments are underway to compare the effects of pH on plant infection by zoospores and sporangia. Implications of these data on management of these quarantine pathogens are discussed.
Full Citation Kong, P.; Lea-Cox, J.D.; Moorman, G.W.; and Hong, C. 2011. Survival of three quarantine pathogens in a simulated aquatic system at different levels of pH. Phytopathology 101:S93.