Phytopathology (1996) 86, S39-S40

E. O'Gara, C. Wilkinson, G.E. St. J. Hardy and J.A. McComb (1996)
The potential for hemi-biotrophic growth of Phytophthora cinnamomi in Eucalyptus marginata
Phytopathology 86 (11 suppl.), S39-S40
Abstract: Collar infection of E. marginata (jarrah) by P. cinnamomi is associated with localized ponding, and results in substantial losses of seedling jarrah from rehabilitated bauxite mines in Western Australia. A preliminary trial established in winter on a rehabilitated mine indicated that zoospores of P. cinnamomi were able to infect the collars of jarrah through unwounded periderm tissue. The trial also indicated that the pathogen was able to colonize the tissue without producing or eliciting lesions. A more detailed study was set up to examine this apparent biotrophic growth. The second trial, also conducted in a rehabilitated mine, involved inoculating jarrah plants with P. cinnamomi in winter or spring, with three harvests at 3 month intervals. Stomatal conductance, xylem pressure potential, height and diameter data were collected regularly. The results indicate that biotrophic growth of P. cinnamomi in jarrah is short-lived. If the pathogen does not progress to a necrotrophic phase it dies within the plant. However, there was little visible indication of the pathogens presence in the plants in the initial stages of infection. The plants continued to transpire at a rate similar to the controls until they were very close to death.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

---

Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Phytophthora cinnamomi	Eucalypt (Eucalyptus)	Australia (Western)