VIEW ARTICLE

Physiology and Biochemistry

Induction and Quantification of Microsclerotia in Rosellinia necatrix. A. Sztejnberg, Senior lecturer, Department of Plant Pathology and Microbiology, The Hebrew University of Jerusalem, Faculty of Agriculture, Rehovot, Israel; Z. Madar(2), and I. Chet(3). (2)(3)Graduate research assistant, and professor, Department of Plant Pathology and Microbiology, The Hebrew University of Jerusalem, Faculty of Agriculture, Rehovot, Israel. Phytopathology 70:525-527. Accepted for publication 19 November 1979. Copyright 1980 The American Phytopathological Society. DOI: 10.1094/Phyto-70-525.

A new method was developed for the quantification of microsclerotia produced by Rosellinia necatrix. The method, which is based on extraction of melanin from microsclerotia, provided a good correlation between the numbers of microsclerotia and the amount of extractable melanin. Red, blue, and fluorescent (daylight-type) illumination induced microsclerotium formation, whereas near-UV light and darkness depressed the morphogenetic process. Scanning electron micrographs revealed that the microsclerotia were undifferentiated, irregular, and rough, being composed of interwoven hyphae.