| Abstract: | Variability in virulence were detected among geographic isolates of Cryphonectria.cubensis (Bruner) Hodges. Inoculation studies of isolates, originally cultured from Brazil, Africa and Hawaii, in provenance of Eucalyptus pellita F. Muell (resistant) and E. saligna Sm. (susceptible) showed that the variation in resistance of Eucalyptus spp. is quantitatively isolate-specific; the variation in virulence quantitatively host-specific. The practical consequences of pathogenic variability of C. cubensis and the strategies of selection and breeding of Eucalyptus for resistance is discussed. |
