The ability of Phytophthora cinnamomi to infect through unwounded and wounded periderm tissue of Eucalyptus marginata

Unwounded and wounded periderm tissue of 1-year old stems of Eucalyptus marginata were infected and lesioned after 5 days' exposure to either mycelium or motile zoospores of Phytophthora cinnamomi. Lesions produced by P. cinnamomi were longer in wounded than in unwounded stems. The inclusion of non-sterile mine site soil with inocula in the unwounded treatments did not affect the rate or extent to which P. cinnamomi colonized E. marginata stem tissue. The ability of P. cinnamomi zoospores to infect unwounded suberized woody tissue of E. marginata, has important implications for mine site rehabilitation in P. cinnamomi infested areas. This is the first study to demonstrate clearly that zoospores of P. cinnamomi can infect and invade unwounded suberized tissue.