Germination of Spores of Cantharellus Cibarius

Abstract

Cantharellus cibarius Fr., one of the most well-known, edible, wild mushrooms of Europe and North America, is generally considered refractory to cultivation under sterile conditions. While some, even experienced, mycologists have failed in their efforts for axenic tissue culture (4, 5), others have been more successful (1, 6, 7, 9, 10). However, to the author's knowledge spore germination has never been observed in' this fungus. By means of a combination of activated charcoal and growing colonies of Rhodotorula glutinis (Fres.) Harrison spore germination in vitro could be induced in Laccaria laccata (Scop. ex Fr.) Berk. et Br. (2), as well as in a few other mycorrhizaforming hymenomycetes (3). The present paper reports the application of this method to the germination of Cantharellus cibarius. Basidiospores of C. cibarius and two other, related species were obtained under sterile conditions from fruit-bodies collected in the neighborhood of Uppsala, during the fall of 1977. They were kept in Petri dishes in darkness at 4 C. The germination tests were made on plates of an autoclave-sterilized agar medium, the spores suspended in sterile, distilled water, and the suspension then spread out over the agar surface, ca. 50,000 spores per plate, by means of a glass rod. The composition of the medium was the same as that earlier described (3), where also some more technical details are given. In certain experimental series activated charcoal and/or living Rhodotorula glutinis cells were added to the plates as shown in FIG. 1. The plates were incubated in darkness at 25 C and inspected for possible germinations once a wk. Just as in the experiments with Laccaria laccata (2), the spores of C. cibarius germinated only in the plates containing both activated charcoal and a Rhodotorula colony. The spores had been kept for only 2 da after deposit. The germination process commenced by the spore