Host-specific strain of Stemphylium causes leaf spot disease of California spinach

Henderson, D; Butler, E; Koike, S

Host-specific strain of Stemphylium causes leaf spot disease of California spinach

Authors

Diana M. Henderson
Edward E. Butler
Steven T. Koike

Authors Affiliations

D.M. Henderson is Agricultural Aide, UC Cooperative Extension, Monterey and Santa Cruz counties; E.E. Butler is Professor Emeritus, Department of Plant Pathology, UC Davis; S.T. Koike is Plant Pathology Farm Advisor, UC Cooperative Extension, Monterey and Santa Cruz counties.

Publication Information

Hilgardia 55(5):31-34. DOI:10.3733/ca.v055n05p31. September 2001.

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Abstract

The California spinach industry has grown dramatically over the past few decades; it now supplies well over 100,000 tons of various high-quality products to consumers. But a new foliar disease. Stemphylium leaf spot, can reduce spinach quality. After identifying this disease, we determined that the pathogen may also be a new, distinct strain of the fungus that is specific to spinach. Inoculation experiments demonstrated that numerous spinach lines are susceptible, including new downy mildew-resistant cultivars. Diagnosing this disease can be difficult because its symptoms often resemble damage from agrochemicals. Growers and pest control advisors should become familiar with the symptoms of the various foliar spinach diseases that occur in California because consumers of this crop tolerate only a small level of leaf spots and defects.

References

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