Host-Parasite Relations in a Mycoparasite III. Morphological and Biochemical Differences in the Parasitic- and Axenic-Culture Spores of Piptocephalis Virginiana

SUMMARY

piptocephalis Virginiana produces long, erect, repeatedly branched sporophores on Choanephora cucurbitarum. The spores from this parasitic culture are characterized by terminal lipid bodies and on germination, on malt-yeast extract medium, produce thin, flexuous, unbranched sporophores bearing a few spores. The axenic-culture spores are without the lipid bodies and in the absence of a host they fail to produce hyphae on germination or fail to germinate. Thin-layer and gas-liquid chromatography show that an extract from the parasitic-culture spores contains more lipids and in addition to palmitic acid, palmitoleic acid, stearic acid, oleic acid, and linoleic acid, it also contains γ-linolenic acid, the latter being not observed in the extract of axenic-culture spores. The significance of the γ-linolenic acid, a characteristic fatty acid of order Mucorales, is discussed.