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Production of Conidia by Cercospora kikuchii in Culture. M. G. Vathakos, Graduate research assistant, Department of Plant Pathology, University of Arkansas, Fayetteville, 72701, Present address of senior author: Kalo Laboratories, Inc., 9233 Ward Parkway, Kansas City, MO 64114; H. J. Walters, professor, Department of Plant Pathology, University of Arkansas, Fayetteville, 72701. Phytopathology 69:832-833. Accepted for publication 26 February 1979. Copyright 1979 The American Phytopathological Society. DOI: 10.1094/Phyto-69-832.

Only vegetative growth of Cercospora kikuchii occurred on standard laboratory media, on agar media prepared from decoctions of carrot leaves, and on agar media prepared from immature and senescent tissues of alfalfa, corn, cotton, and wheat. Leaf decoction agar from immature soybeans yielded few conidiophores, but agar media prepared from senescent soybean plants (SSPA) yielded abundant conidiophores. The fungus sporulated sparsely on SSPA in continuous darkness, but sporulated profusely when exposed to several light regimes. Sporulation was most abundant in cultures exposed 8 hr/day to illumination from Gro-Lux lamps at room temperature. More spores were produced on cultures grown from spore transfers than from those grown from mycelial transfers. Transfer of spores by tapping the bottom of an inverted petri plate containing a sporulating culture over a plate of fresh SSPA medium produced the maximum numbers of spores per plate.