Characterization of putative in vitro hybrids within the genus Flammulina

Abstract

The genus Flammulina (Basidiomycetes, Agaricales, Tricholomataceae) includes a group of saprobic mushrooms that grow in the wild and are also cultivated and sold commercially throughout the world under the name "enoki" or "enoki-take". Until the 1960s, the genus Flammulina was believed to consist of a single species with a pan-Northern Hemisphere distribution. Flammulina velutipes (Curt.: Fr.) Singer was more or less applied to all collections in the genus whether naturally or commercially produced (Buchanan 1993) until the mid 1960s. In the interim, 14 additional taxa have been described in Flammulina. Knowledge of hybridization within the Flammulina velutipes group is crucial to the mushroom growing industry as it attempts to identify higher yielding strains. The main goal of this study is to determine if these interspecific hybrids of Flammulina are "true" hybrids rather than "transitory" hybrids? In order to test this hypothesis, three different systematic approaches were used; morphological analyses, mating studies, and molecular characterization. As a result, there was enough morphological variation to suggest that these are "true" hybrids. However, observations of the ITS1-5.8s-ITS2 region suggests that these are either homogenized ribosomal repeats, suggesting that these are "true" hybrids, or that they are PCR chimeras.

Date of Award	2006
Original language	American English
Awarding Institution	Eastern Illinois University
Supervisor	Andrew S. Methven (Supervisor)