Plant Disease Diagnostics and Management

Hannah Rivedal preparing potatoes for proof-of-virulence research.

Put to the Test

I run the plant disease diagnostic clinic located at the Hermiston Agricultural Research and Extension Center. An important part of plant production is managing diseases and pests. I provide testing and diagnostic services for the irrigated vegetable growers of the lower Columbia Basin and eastern Oregon. I use molecular methods to quickly and accurately detect fungal, viral, and bacterial pathogens because, just like humans, plants get sick, too! I also use classic techniques to culture organisms, like growing bacteria and fungi on Petri plates, so I can identify plant pathogens using a microscope. Finally, I provide growers with a report of the tests I conducted, a diagnosis of the problem afflicting their plants, and recommendations on how to manage the problem this growing season and in future growing seasons.

Bacterial soft rot (lenticel rot) of potato.
A common disease in storage potatoes.
Viral mosaic symptoms expressed in potato leaves.
This can lead to reduced yield of tubers after harvest.

Rooting Out the Problem

I decided to pursue a career in plant health, specifically disease diagnosis and plant pathology, because I love the challenge of identifying the pathogens causing a plant disease and the direct impact I can have with my work. I get to use many of the skills I developed in microbiology, agronomy and plant pathology classes to isolate and identify the pathogens causing problems for growers. Then I can inform the grower about their options for disease management. The results from my work are often used immediately to improve the health and productivity of the plants grown in our agricultural system.

Corn smut of sweet corn. A startling disease issue that appears in the Columbia Basin on rare occasion.

A Good Defense

Growers work hard to produce the best possible crops to feed all of us. Plant disease management is an ongoing, evolving aspect of all farming operations. My work, providing accurate and timely diagnosis of plant diseases, saves time, money, and improves harvestable crop yield and quality.

Cream of the Crop

I work with a variety of people at the Hermiston Agricultural Research and Extension Center including Dr. Ken Frost (Department of Botany and Plant Pathology), Cassandra FunkeVictoria Skillman, and Dr. Bryn Evin.

Sexual reproductive spore structures called chasmothecia on wheat leaves grown in irrigated fields.
A new crop for Oregon - Hemp! Diagnosing diseases on new crops can be challenging and exciting. This hemp has a viral infection called Curly Top disease.
Ken Frost and Victoria Skillman evaluating potatoes that were artificially infected with soft rot bacteria. This is an important disease that we study in depth in the lab.