Molecular evidence for the anamorph-teleomorph connection in Cordyceps sinensis

Cordyceps sinensis, the caterpillar fungus in traditional Chinese medicine, has been intensively collected from nature in recent years. As a result, t he establishment of the anamorph of this species has become important for l arge-scale culture to meet increasing demand for medicinal use and to ease exploitation of natural populations. To establish a reliable connection bet ween the teleomorph and anamorph stages, the ITS nrDNA sequences were seque nced from both the stroma of the telemorph and cultures of the anamorph. Ob servations of microcyclic conidiation were also made on germinated ascospor es and compared with the anamorph in culture. Hirsutella sinensis was confi rmed as the anamorph of C. sinensis by both DNA sequences and microcyclic c onidiation. Two recently described species, C. multiaxialis and C. nepalens is, were shown to share identical or almost identical ITS sequences with C. sinensis. These minor variations were considered to be within the range of variation exhibited within a species, but representing different populatio ns. Sequences from other Cordyceps species included in this study exhibited considerable differences from each other. Therefore, these three entities are probably conspecific, and the names should be regarded as synonymous. T he morphological characters used in the description of the two new species are discussed. It is suggested that ITS sequences provided useful informati on on establishing the anamorph-telemorph connection and assisting in the d elimitation of species within Cordyceps.