Infection Studies withPhaeoseptoria eucalyptiandConiothyrium ovatumonEucalyptusspp.

Abstract

Phaeoseptoria eucalypti and Coniothyrium ovatum have recently been associated with leaf lesions on Eucalyptus spp. in South Africa. P. eucalypti caused severe defoliation of E. camaldulensis and E. grandis, prominent lesions on shoots of E. camaldulensis, and retarded the growth of E. nitens. It infected all the species tested in the subgenus Symphyomyrtus, but not E. citriodora of the subgenus Corymbia. Conidia of C. ovatum germinated on all species tested, but no infection occurred. This study has shown that P. eucalypti can be a serious nursery pathogen, but that C. ovatum would pose no threat to Eucalyptus spp. important in this country.