Variation in Nectria radicicola and its anamorph, Cylindrocarpon destructans

Abstract

Nectria radicicola is characterized by its distinctive perithecial morphology and anatomy, and by its anamorph, Cylindrocarpon destructans. Several collections readily identified as N. radicicola were made in New Zealand, Indonesia, and Venezuela. Pure cultures derived from ascospores isolated from these collections showed considerable variation in cultural and morphological characteristics. The anamorph, Cylindrocarpon destructans var. destructans, is characterized by a fast growth rate and by the formation of discrete chlamydospores. It is distinguished from C. destructans var. coprosmae (C. Booth) comb. nov., which has a slower growth rate and does not form discrete chlamydospores. Cylindrocarpon destructans var. coprosmae is the anamorph of N. radicicola var. coprosmae (Dingley) stat. nov. Cylindrocarpon macroconidialis sp. nov., the anamorph of N. radicicola var. nuicroconidialis var. nov., is distinguished by larger macroconidia. Other variants of C. destructans are discussed but are not given separate taxonomic status because they are based on single collections. Nectria austroradicicota sp. nov. is distinguished from N. radicicola by having much larger ascospores and by its anamorph, C. auslrodestruclans sp. nov.