James W. Lorbeer, whose research on diseases of onion and other vegetables grown in organic soils aided growers in New York state and around the world, died Oct. 5, 2023, in Ithaca. A professor emeritus of plant pathology, Lorbeer was 91.

Lorbeer was born and raised on his family’s citrus farm in Ventura County, California, and his upbringing affected his research direction, said Gary Bergstrom, professor emeritus of plant pathology and a colleague of Lorbeer.

“Agriculture was in Jim’s blood, and this influenced his career choice, and especially his motivation to develop useful solutions for farmers,” Bergstrom said. “His scientific travels took him to every continent except Antarctica. At the same time, until his death, he oversaw management of orange groves in California.”

Lorbeer’s research focused on the causes and management of vegetable crop diseases, especially for crops grown in organic soils. Lorbeer was internationally recognized for his groundbreaking research and publications on diseases of onion, Bergstrom said, especially fungal and bacterial infections that cause crop-devastating diseases like purple blotch disease, neck rot, bulb rot and leaf blight. He collaborated with farmers, researchers, and public and private agencies to develop disease-resistant onion varieties, disease prediction systems, effective fungal control strategies and modified cropping practices to reduce disease impacts.

Lorbeer was born Oct. 30, 1931. He received his bachelor’s degree from Pomona College, his master’s degree from the University of Washington, Seattle, and his Ph.D. in plant pathology from the University of California, Berkeley. He joined the Cornell faculty as an assistant professor in 1960 and retired in 2010.

Lorbeer received the American Phytopathological Society Northeastern Division Award for Applied Research in 1991 and the Orange County (New York) Vegetable Improvement Cooperative Association Award in 1993. He published more than 300 articles in scientific and trade journals as well as numerous book chapters. His research was supported by grants from the U.S. Department of Agriculture, the New York State Department of Agriculture and Markets and private agricultural companies.

Lorbeer was also an effective and caring teacher and adviser, said George Abawi, M.S. ’65, Ph.D. ’71, professor emeritus of plant pathology and plant-microbe biology. Lorbeer taught courses in plant pathology and mycology and served as director of graduate studies in plant pathology. Abawi was advised by Lorbeer during his graduate studies before becoming his colleague.

“Jim was an excellent teacher and adviser throughout his career,” Abawi said. “He cared about all of his students, he introduced them to all the scientists he knew at meetings, and he always made sure they got their shares of whatever resources were available to them in the department and the graduate school. He was truly engaging, respectful and most helpful to all.”

Lorbeer’s research and outreach work benefited onion growers, consumers, fellow scientists and the environment, Abawi said.

“His research always addressed practical and ongoing production problems, thus growers were the primary beneficiaries of his research results,” he said. “However, the integrated pest management approaches Jim advocated also benefited the environment and reduced production costs, which benefited consumers.”

Lorbeer is survived by his wife of 59 years, Susanne T. Perrault Lorbeer.

Krisy Gashler is a writer for the College of Agriculture and Life Sciences.