Project Overview

Reports

Commodities

Target Pests

Practices

Soilborne diseases are an especially challenging problem in perennial crops. In hop, one such disease is Fusarium canker, caused primarily by the fungus Fusarium sambucinum, so named because it causes a canker that can entirely girdle stems and lead to bines wilting and dying before harvest (19) The disease also cause a rot of the perennial crown and rootstock that can reduces vigor or kill entire plants, sometimes leading to catastrophic losses of entire plantings (26). Potentially even more impactful, F. sambucinum has the ability to produce a suite of mycotoxins of concern for animal and human health (9), including the potent trichothecenes (2, 20). The fungus has a broad host range that is reported to include beet, various Brassica crops, and potato (6, 8). Canker is ubiquitous in hop production and historically was considered a minor problem that only occasionally caused economic damage. However, severe occurrences of the disease are increasingly reported (29), particularly in Washington State where approximately three quarters of U.S. hop production occurs. Yet, relatively little is known about basic aspects of biology of the disease and its management, especially on hop.

This Project Initiation will generate and extend foundational knowledge on Fusarium sambucinum and Fusarium canker to inform potential cover crops and rotational crops, cultural control measures, and basic aspect of disease biology that underpin sound management. Specifically, we will:

• Characterize populations of Fusarium sambucinum from diverse hosts to infer host specialization of hop-derived isolates;
• Quantify the impact of varying irrigation regimes on disease development; and
• Broadly communicate results to stakeholder partners to accelerate learning and maximize the impact of this project.

These objectives align with multiple documented priorities of stakeholders, the Western IPM Center, and the National Roadmap for IPM. The project is timely, leverages our existing expertise and resources, and will provide the knowledge base needed to guide future research, extension, and provide evidence-based management to producers. Our recent research discoveries and stakeholder partnerships provide the foundations for this and future efforts that this Project Initiation proposal will enable.

The overall objective of this Initiation Project is to generate and extend foundational knowledge on Fusarium sambucinum and its disease on hop and potentially other crops affected by this pathogen. Our specific objectives are to:

• Characterize populations of Fusarium sambucinum from diverse hosts to infer host specialization of hop-derived isolates;
• Quantify the impact of varying irrigation regimes on disease development; and
• Broadly communicate results to stakeholder partners to accelerate learning and maximize the impact of this project.

These objectives are timely, leverage our existing expertise and resources, and will provide the knowledge base needed to guide future research, extension, and sound recommendations to growers, crop advisers, and other stakeholders.