VIEW ARTICLE

Physiology and Biochemistry

Sexual Reproduction of Pythium aphanidermatum: Stimulation by Phospholipids. W. H. Ko, Professor, Department of Plant Pathology, University of Hawaii, Beaumont Agricultural Research Center, Hilo 96720; Phytopathology 76:1159-1160. Accepted for publication 27 March 1986. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/Phyto-76-1159.

In a chemically defined liquid medium, lecithins obtained from egg yolk (type III-E) were as effective as those obtained from soybean in inducing oospore formation of Pythium aphanidermatum. l-α-phosphatidyleth-anolamine from soybean also induced sexual reproduction, but l-α-phosphatidylinositol from soybean or l-α-phosphatidyl-l-serine from bovine brain did not. Dioleoyl- and dilinoleoyl-l-α-phosphatidylcholine of synthetic lecithins also induced oospore formation in P. aphanidermatum. Results suggest that the activity of lecithins is determined by the type and position of fatty acids in the molecular structure. The activity of lecithins was partially replaced by triolein, diolein, dipalmitin, and trilinolein. However, the activity of these glycerides could not be replaced by their corresponding fatty acids.