Isolates of C. finzbriata from different hosts and geographic locations diftered in colony type, pathogenicity, growth rate, and conidial states, but were similar in certain other characters, including an absolute requirement of thiamine for the production of perithecia, opti~num te~nperature for growth, perithecial morphology, and sexual behavior.The amount of cross-fertility between strains from different hosts and geographic locations was determined. The significance of ~norphological differences and cross-fertility between strains is discussed ill relationship t o the taxonomy of C. fit~ibriata and the related species C. nzonilifornzis (Hedge.) C. hloreau. C. variospora Davids. is co~lsidered a synonym of C. fivrbrzata.

Beginning in 1997, a new disease of spinach was found in the Salinas Valley, Monterey County, CA. Initial symptoms were leaf spots that were 2 to 5 mm in diameter, circular, and gray-green in color. Spots later enlarged, turned tan in color, and became dry and papery in texture, resembling phytotoxicity due to agrichemicals. Although fungal signs were generally absent from the spots, Stemphylium botryosum was consistently isolated and caused identical symptoms when inoculated onto 20 spinach cultivars. Three isolates did not cause disease symptoms when inoculated onto other crop plants representing 16 different genera and a Chenopodium weed species. A fourth isolate showed similar results with the exception of small leaf spots occurring on inoculated fava bean. Isolates produced a Pleospora herbarum teleomorph after 7 months incubation at 5°C. Preliminary experiments with cell-free culture filtrates indicated that phytotoxins apparently were not produced by these isolates. This is the first report of a foliar spinach disease caused by S. botryosum.

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