VIEW ARTICLE

6a-Hydroxyphaseollin: an Antifungal Chemical Induced in Soybean Hypocotyls by Phytophthora megasperma var. sojae. N. T. Keen, Assistant Professor, Department of Plant Pathology, University of California, Riverside 92502; J. J. Sims(2), D. C. Erwin(3), E. Rice(4), and J. E. Partridge(5). (2)(3)(5)Associate Professor, Professors, and Graduate Research Assistant, respectively, Department of Plant Pathology, University of California, Riverside 92502, (4)Professor is associated with the Department of Biochemistry, California State Polytechnic College, Pomona 91166. Phytopathology 61:1084-1089. Accepted for publication 7 April 1971. DOI: 10.1094/Phyto-61-1084.

6a-hydroxyphaseollin (HP), a new hydroxypterocarpan, was isolated from soybean hypocotyls challenged with Phytophthora megasperma var. sojae. Hydroxyphaseollin was not detected in extracts from unchallenged hypocotyls, and was the only induced antifungal compound detected in bioassays of hypocotyl extracts from challenged plants. A gas-liquid chromatographic analysis was devised for HP which showed that it accumulated to about 10-fold higher concentrations in inoculated hypocotyls of monogenically resistant soybeans than in a near-isogenic susceptible line.