Induction of sporulation of fungi isolated from Dactylis glomerata seed by exposure to near-ultraviolet radiation

SUMMARY Pure cultures of fifty‐two species of plant pathogenic and saprophytic fungi isolated from orchard (cock's‐foot) grass seed (Dactylis glomerata L.) were incubated either in total darkness or exposed to a diurnal cycle of near‐ultraviolet (NUV) radiation (12 h NUV/12 h darkness). Twenty‐four species sporulated only after exposure to NUV including seven species of Drechslera , five species of Fusarium , as well as species olAscochyta, Photna, Septoria, Pyrenochaeta, Rhynchophoma and Stagonospora; six species sporulated moderately in darkness but more profusely following exposure to NUV; twenty species sporulated whether they were irradiated or not; and only two species failed to sporulate. To assess the pathogenic fungal microflora of orchard grass seed accurately, seeds should be incubated under a daily regime that includes NUV to induce sporulation.