Ophiosphaerella herpotricha, a Cause of Spring Dead Spot of Bermudagrass in Kansas. N. A. Tisserat, Assistant Professor, Department of Plant Pathology, Throckmorton Hall, Kansas State University, Manhattan 66506. J. C. Pair, and A. Nus. Professor, Department of Horticulture, Horticultural Research Center, Kansas State University, Wichita 67233, and Research Assistant, Department of Plant Pathology, Throckmorton Hall, Kansas State University, Manhattan 66506. Plant Dis. 73:933-937. Accepted for publication 6 May 1989. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1989. DOI: 10.1094/PD-73-0933.

Ophiosphaerella herpotricha was consistently isolated from stolons and roots of bermudagrass (Cynodon dactylon) affected with spring dead spot (SDS) in Kansas. The fungus was sterile in culture but occasionally produced fertile pseudothecia on inoculated plants. Optimal growth rates on potato-dextrose agar occurred between 20 and 25 C. In greenhouse tests, inoculation with O. herpotricha significantly increased root discoloration ratings and, in most experiments, decreased root weights of bermudagrass. The fungus colonized root tissue at soil temperatures of 15 and 25 C. In field tests, symptoms of SDS were reproduced on 18 clones or cultivars 1–2 yr after inoculation with O. herpotricha.

Keyword(s): Leptosphaeria korrae, Gaeumannomyces incrustans, Gaeumannomyces graminis var. graminis.