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

Koike, S; Henderson, D; Butler, E

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

Authors

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

Authors Affiliations

S.T. Koike is Plant Pathology Farm Advisor, UC Cooperative Extension, Monterey and Santa Cruz counties; 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.

Publication Information

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

PDF of full article, Cite this article

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

[CASS] California Agricultural Statistics Service. County Agricultural Commissioners' Data. Sacramento, CA. 2000. www.nass.usda.gov/ca/bul/agcom/indexcac.htm .

Correll JC, Morelock TE, Black MC, et al. Economically important diseases of spinach. Plant Dis. 1994. 78:653-60.

Koike ST, Correll JC. First report of spinach anthracnose caused by Colletotrichum dematium in California. Plant Dis. 1993. 77:318-

Koike ST, Henderson DM, Butler EE. Leaf spot dlsease of spinach in California caused by Stemphylium botryosum. Plant Dis. 2001. 85:126-30. https://doi.org/10.1094/PDIS.2001.85.2.126

Koike ST, Smith RF, Schulbach KF. Resistant cultivars, fungicides combat downy mildew of spinach. Cal Ag. 1992. 46(2):29-31.

LeStrange M, Koike ST, Valencia J, Chaney W. Spinach production in California. Vegetable Production Series. 1996. UC DANR Pub 7212. 4 p.

Padhi B, Snyder WC. Stemphylium leaf spot of lettuce. Phytopath. 1954. 44:175-80.

Raid RN., Davis RM, Subbarao KV, Raid RN, Kurtz EA. Stemphylium leaf spot. Compendium of Lettuce Diseases. 1997. St. Paul, MN: American Phytopathological Society Press. pp.25-6.

Rotem J, Bashi E. A review of the present status of the Stemphylium complex in tomato foliage. Phytoparasitica. 1977. 5:45-58.

Rotem J, Cohen Y, Wahl I. A new tomato foliage disease in Israel caused by Stemphylium botryosum.. Canadian J Plant Sci. 1966. 46:265-70.

Wiltshire SP. The original and modern concepts of Stemphylium. Trans Brit Mycol Soc. 1938. 21:211-39.

Also in this issue:

Biology and ecology of Euseius scutalis (Athias-Henriot) (Acarina: Phytoseiidae)

Research and extension reduce impact of California energy crunch

Genetically engineered tomato grows in salty water

Study reveals risk factors for teen suicide

UC scientists help growers cope with energy crunch

Methane generators turn agricultural waste into energy

BIFS reports potential for chemical reductions in crops and dairy

BIOS and conventional almond orchard management compared

Armored scale insecticide resistance challenges San Joaquin Valley citrus growers

Managing manure and conserving predators helps control flies in caged-layer poultry systems

Rust disease continues to threaten California garlic crop

Interpersonal communication tops concerns of farm supervisors

One-pass tillage equipment outstrips conventional tillage method