Abstract

Sclerotinia stem rot occurs sporadically in Australian canola and is caused by Sclerotinia sclerotiorum (Lib.) de Bary. During the canola flowering period of 1998, canola was surveyed throughout New South Wales for the incidence of Sclerotinia species on petals. While scoring for S. sclerotiorum, several isolates were later identified as Sclerotinia minor Jagger, rather than S. sclerotiorum. Although S. minor has been previously identified on canola, there is only evidence that S. minor infects plants mycelogenically. Its presence on canola petals and pathogenicity on canola suggests a possible airborne mode of infection by ascospores.