Getting the Diagnosis Right: Guam Workshop Focuses on Foliar Fungal Diseases

September 22, 2021
Workshop participants learn to scout for plant diseases during a field trip to Ernie Wusstig’s farm. Photo courtesy of University of Guam.

In farming, as in medicine, an accurate diagnosis is critical. For a doctor to prescribe the correct treatment, they need to know the specific disease causing a patient’s symptoms. The same is true for growers. When they see disease symptoms in a field, they need to know the underlying cause in order to correctly treat their crop.

A recent workshop in Guam helped improve the ability of agricultural professionals and others in the Pacific islands to make those diagnoses. Funded by the Western Sustainable Agriculture Research and Education program, the four-day workshop trained 14 people from Guam and the Northern Marianas Islands on how to identify fungal leaf pathogens and the diseases they cause.

University of Guam plant pathologist Robert Schlub organized the event, with partners from the University of Georgia and the University of the Philippines.

“A concept I emphasized throughout the workshop is that all knowledge is power and knowing what is not causing a plant symptom can be nearly as important as knowing the actual cause,” Schlub explained. “For example, knowing that a leaf spot is not caused by a fungus is enough information to keep a grower from applying unnecessary applications of a fungicide.”

The training in August included classroom instruction, laboratory exercises and field outings.

“We concentrated on foliar fungal diseases because they are the diseases most commonly reported and often misidentified,” Schlub explained. “I wanted the trainees to learn the basic skills necessary to differentiate among similar and often confused symptoms caused by foliar pathogens and also to gain the skills necessary to tell one pathogen from another.”

Trainers from Georgia and the Philippines gave the workshop broader perspective and helped the workshop attendees gain knowledge and experience to feel comfortable in examining plant specimens under a microscope or using a hand-lens during a field-diagnosis process. Attendees also learned how to make the best use of the various diagnostic resources available at the University of Guam.  

Plant pathologist Robert Kemerait from the University of Georgia was one of the workshop trainers.

“Having been Extension for over 21 years, I can say that this workshop, which included presentations, field trips and work in the lab with diseased samples, was a good or better than any I have ever attended,” Kemerait said. “Prior to this, my knowledge of Guam was largely historical, but now I have a tremendous appreciation for Guam, the people of Guam, the University of Guam, and the plant disease issues faced in Guam and the Northern Mariana Islands.”

The workshop ended with a real-life final exam for the participants.

“On the last day, the public was invited to bring in samples or plant disease questions to the clinic for diagnosis,” Schlub said. “Not only was that beneficial for the members of the public who came, it was a great experience for the workshop participants. There was great interaction and discussion between the groups.”  

The next step is making the training material available to more people.

“As part of the SARE grant’s objective, the lectures and resource materials used during the workshop will be posted on a University of Guam website and made available to the trainees and the public,” Schlub said. “I’m going to retire in 2022 and knew this workshop would be one of my last opportunities to pass on some of my knowledge to other ag professionals on Guam. My hope is these workshop materials will be the framework for future training courses and helpful for the next generation of plant pathologist and diagnosticians.” 

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Topics: Demonstration, Farmer to Farmer, Workshop
Related Locations: Guam, Micronesia, Northern Mariana Islands, West