In August 2012, wilted hop bines were observed in a yard near Seneca Castle, New York, affecting 10 to 20% of the plants. Affected bines had a dark stem discoloration and wilted leaves that remained attached after bines were killed. Dark brown to black, erumpent pycnidia were aggregated in the...
Downy mildew (caused by Pseudoperonospora humuli) causes significant losses in hop (Humulus lupulus L.) cone yield and quality, and potential crown death. Breeding for resistance has proved difficult presumably because of the highly quantitative nature of genetic control over expression. The objective of this study was to utilize multiple environments...
Podosphaera macularis, the causal agent of hop powdery mildew, is known to produce chasmothecia (formerly cleistothecia) in eastern North America and Europe. Ascocarps have not yet been reported from the Pacific Northwestern region of North America. Reasons for the apparent absence of chasmothecia in the Pacific Northwest were unknown. This...
Hop downy mildew (DM) is an obligate parasite causing severe losses in hop if not controlled. Resistance to this pathogen is a primary goal for hop breeding programs. The objective of this study was to identify QTLs linked to DM resistance. Next-generation-sequencing was performed on a mapping population segregating for...
In June 2009, wilted hop bines were observed in a yard in Marion County, OR. The wilt was associated with a stem rot that occurred ∽1 m from the ground near the point where bines are tied together for horticultural purposes. Samples of affected stems were submitted to the Oregon...