Diseases

Powdery mildew of hop

Humulus lupulus L.

A fungal disease of hop caused by the pathogen Podosphaera macularis, affecting leaves, shoots, and cones with a white powdery coating. It leads to deformation of plant organs, weight loss, and reduced quality characteristics of the raw material.

In the reference 52 varieties crop Common hop, where this is mentioned in the description.

The causative agent is the fungus Podosphaera macularis, which manifests as a superficial powdery coating. Unlike downy mildew, the disease causes deformation and desiccation of hop cones, which critically reduces their value for the brewing industry.

Pathogen populations are characterized by high variability and the presence of physiological races that overcome genetic resistance. Breeding programs utilize R-genes (R1–R6, Rb); however, resistance based on a single dominant gene often proves to be short-lived, necessitating a transition to a polygenic protection strategy.

General information about the subject — on the page Powdery mildew.

Sources8

Varieties of Common hop mentioned in the description

Selection based on the description text, not on official evaluation: these data are absent from registers. For specific variety details, please refer to its profile.