Comparative Performance of Fungicides in Management of Phytophthora Root Rot on Boxwood

Nursery growers rely on fungicides to manage root rot disease of boxwood caused by Phytophthora nicotianae and P. cinnamomi. Repeated use the same fungicide may lead resistance. In this study, pyraclostrobin + cyazofamid (Empress Segway), ametoctradin dimethomorph (Orvego), alternated with (Orvego alt Empress), fluxapyroxad Orkestra), oxathiapiprolin (Segovis) were evaluated for their efficacy in managing under greenhouse conditions Tennessee. One-year-old container-grown ‘Green Velvet’ plants inoculated or cinnamomi . The first applications treatments made preventatively as a drench 48 h before pathogen inoculation. Following inoculation, four performed 14-day intervals. Initial final plant height width measured. Total fresh weight measured at end trials, severity (0% 100% roots affected) recovery. All significantly reduced recovery Ametoctradin Empress) provided similar protection against that single application (Orvego) (Segovis). For , fluzapyroxad Orkestra) was found be effective either one two trials. Effects growth such height, width, total, not significant. These findings will useful nursery selecting right program management