The hop downy mildew pathogen Pseudoperonospora humuli

Area of Science:

• Plant Pathology
• Oomycete Biology
• Horticultural Science

Background:

• Pseudoperonospora humuli causes downy mildew, a major disease of cultivated hop (Humulus lupulus).
• The pathogen overwinters in hop crowns and roots, leading to significant crop losses globally.
• Disease management relies on sanitation, resistant cultivars, and fungicides, but faces challenges from host resistance scarcity and fungicide resistance.

Purpose of the Study:

• To review current knowledge on hop downy mildew, including symptoms, life cycle, and management.
• To discuss recent advancements in genomics and effector discovery for disease control.
• To explore future prospects for integrated disease management strategies.

Main Methods:

• Literature review of scientific publications and resources on hop downy mildew.
• Synthesis of information on disease epidemiology, pathogen biology, and control measures.
• Analysis of current and emerging strategies for disease management, including genomic approaches.

Main Results:

• Hop downy mildew presents characteristic symptoms like chlorotic spikes, leaf lesions, and cone discoloration.
• The infection cycle involves overwintering mycelium, sporangia dispersal, and zoospore infection.
• Effective management integrates sanitation, resistant cultivars, timely fungicide applications, and forecasting systems.

Conclusions:

• Integrated disease management is crucial for controlling hop downy mildew.
• Genomic resources and effector discovery offer promising avenues for developing novel control strategies.
• Continued research is needed to address challenges like fungicide resistance and enhance disease resistance in hop cultivars.