A Synthetic Medium for Mass Production of Pycnidiospores of Stenocarpella Species. M. A. Morant, Department of Agriculture, University of Maryland Eastern Shore, Princess Anne 21853. H. L. Warren, and S. K. Von Qualen. Department of Plant Pathology, Physiology and Weed Science, Virginia Polytechnic Institute and State University, Blacksburg 24061; and Former Research Assistant, Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907. Plant Dis. 77:424-426. Accepted for publication 11 January 1993. 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, 1993. DOI: 10.1094/PD-77-0424.

Sporulation and vegetative growth of Stenocarpella maydis and S. macrospora were evaluated by growing the organisms in basal mineral salts medium amended with sucrose (0–30 g/L) and biotin (0–50 mg/L) for 28 days at 23 C under constant illumination. Sucrose at 5 or 10 g/L and biotin at 6 or 8 mg/L yielded the largest quantity of pycnidiospores of each organism. Sporulation of S. maydis, however, was higher than that of S. macrospora at all concentrations of biotin, although 6 mg/L gave the largest number of spores compared with biotin-less medium. Pycnidiospore concentrations of S. maydis and S. macrospora in media amended with 10 g/L of sucrose and 6 mg/L of biotin were 0.73 × 10⁶ and 0 per milliliter, respectively. In the absence of biotin, pycnidiospore concentrations were 3.0 × 10⁶ and 0.31 × 10⁶, respectively. Production of mycelia was enhanced by biotin but was independent of its concentration, and there was an inverse relationship between vegetative growth and sporulation for each organism.

Keyword(s): corn.