Morphological, Cultural and Mating Studies on Atkinsonella, Including A. Texensis

ABSTRACT

Comparative morphological and cultural studies in strains of Atkinsonella (Clavicipitaceae, tribe Balansieae) from all known host grasses (Danthonia compressa, D. spicata, D. sericea and Stipa leucotricha) revealed a number of characteristics distinguishing between strains from the allopatric host genera Danthonia and Stipa. Differences were found in stroma size, in morphology of the Ephelis anamorph, and in growth rates and colony characteristics in culture. The Stipa form of Atkinsonella is recognized as a separate species, A. texensis. Conidial transfers between stromata from different clones of D. spicata indicated a heterothallic mating system in A. hypoxylon. Distinctive characteristics of Atkinsonella, including ascospore germination pattern, warrant recognition of Atkinsonella as a distinct genus from Balansia.

Key Words:

• Atkinsonella hypoxylon
• A. texensis
• Balansieae
• heterothallism
• ascospore germination