Plant Pathology

Themis J. Michailides

Plant pathology, fungal disease, epidemiology, latent infection, disease management, fungicide resistance, mycotoxins, aflatoxins

Plant Pathology, Kearney Agricultural Research & Extension Center (KARE), Parlier, CA

Dr. Michailides is a leading authority in fungal fruit tree pathology and is nationally and internationally recognized for his innovative ecological, epidemiological and plant disease management studies of devastating diseases of fruit crops such as the brown rot of stone fruit (pre-harvest and post-harvest), Botrytis gray mold of kiwifruit, pomegranate, and pistachio, fig endosepsis and smut of figs, black heart of pomegranate, Botryosphaeria blight and canker of pistachio, almond, and walnut, and aflatoxin contamination of nut crops and figs. We are doing pioneering work on resistance mechanisms of Alternaria alternata and Botrytis cinerea to various fungicides. Our studies also involve the phylogenetic analysis and taxonomy of plant pathogens attacking fruit and nut tree crops and determination of resistance of various tree cultivars to plant diseases.  We focused on detection of pathogens’ latent infections; these studies helped develop practical techniques that are used now commercially by private laboratories to help pest control advisers, California growers, and growers worldwide to make wise decisions regarding disease management. A very recent major accomplishment was the registration of an atoxigenic Aspergillus flavus strain AF36 (inoculum carrier wheat seed) in pistachio to reduce aflatoxin contamination of pistachio. About 77,000 acres of pistachios were treated with AF36 in 2012 for the first time and about 150,000 to 200,000 acres in 2013, 2014, and 2015. We also performed studies to expand the label of AF36 registration for almonds and figs. Registration was obtained for the atoxigenic Aspergillus flavus AF36 Prevail (inoculum carrier sorghum seed) in early August 2017. Funding and collaborations on these projects include the California Pistachio Research Board, the Almond Board of California, the California Fig Institute and other Agricultural Industries, the California Department of Food and Agriculture, and the Agricultural Research Service (ARS) of the USDA. In addition, there is a crew of 8 to 10 people doing research in my plant pathology projects at the KARE Center, so there is ample opportunity for interaction with a variety of individuals in an area of fundamental and traditional plant pathology.

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Contact:; 559-646-6546; 559-273-8640