Steve Koike

After 28 years of service, Steven T. Koike, UC Cooperative Extension plant pathology advisor in Monterey and Santa Cruz counties, plans to retire from the University of California at the end of 2017.

Koike, who joined the UCCE Monterey County office in 1989, conducts an extension research and education program on diseases of vegetable, fruit and ornamental crops. He focused on diagnosing plant problems, investigating the epidemiology of diseases, evaluating fungicides and other disease control methods, identifying and characterizing new diseases, and advising clientele on disease management approaches.

Koike created and operated the university's only county-based, fully equipped diagnostic lab for plant diseases, located in Salinas. 

Using his diagnostic skills, Koike was instrumental in identifying a new virus that damaged the celery crop on California's central coast from 2007 through 2009. Tracing the virus back to poison hemlock, he and Oleg Daugovish, UCCE advisor in Ventura County, advised growers to remove the weed to protect celery, parsley and cilantro crops.

In 2009, downy mildew began causing spinach leaves to turn bright yellow and then brown in the Salinas Valley. By testing samples of diseased spinach from throughout the state, Koike and his counterparts at the University of Arkansas determined there were four new races of the mildew causing the outbreaks. Revelation of the new fungus strains in 2012 helped the industry develop resistant spinach cultivars.

In response to foodborne illness outbreaks, he collaborated on field studies involving foodborne bacterial pathogens, including E. coli survival in vegetable fields.

During his UCCE career, Koike published 381 peer-reviewed and 711 non-peer-reviewed publications, including his 450-page book Vegetable Diseases: A Color Handbook.

Koike has received many awards, including the UC ANR Assembly Council Fellowship for Advanced Studies in 1997; a 1999 Resolution from the Monterey County Board of Supervisors for excellence in service and research; 2000 Award for Outstanding Achievement from the California Friends of Agricultural Extension; 2005 Joseph M. Ogawa Research & Teaching Endowment Award; the Milton D. and Mary M. Miller Plant Science Awards in 1993, 1998 and 2006, from the UC Davis Department of Plant Science; 2011 Oscar Lorenz Award, Dept. Plant Sciences, UC Davis; UC ANR Distinguished Service Awards for Outstanding Research in 2002 and 2011; and the American Phytopathological Society's National Award for Excellence in Extension Plant Pathology in 2013.

In announcing his retirement, Koike thanked the many people who assisted and encouraged him in his extension career: growers, pest control advisers and other agricultural professionals; fellow UCCE academics from throughout the state; research technicians and support staff from his Salinas office and other university and USDA researchers.

In January 2018, Koike will become the lab director for TriCal Diagnostics, which is building a new laboratory, in Hollister. His new position with TriCal Diagnostics will involve operating a commercial diagnostic lab for plant diseases, supporting research on soil-borne plant pathogens, and providing plant pathology information to clientele who grow or work with various agricultural commodities.