Skip to content

Phytophthora Root Rot of Wollemi Pine

Edward Liew, Patricia Meagher, Maureen Phelan
Project sponsors:
The Royal Botanic Gardens and Domain Trust, OEH Saving Our Species program, Royalties from Wollemi Pine sales

Project aims

To test and compare the efficacy of various phosphonate treatment methods to control Phytophthora Root Rot of Wollemi Pine. This includes soil drenching and bark painting on young cuttings and mature trees.

Project Summary

The endangered Wollemi Pine is highly susceptible to Phytophthora root rot. Various disease management measures have been introduced at the natural Wollemi Pine site where Phytophthora cinnamomi has been detected. Phosphonate (or phosphite), a chemical for managing Phytophthora diseases, is well-established for treating trees showing disease symptoms. Although the recommended mode of treatment includes foliar spray, soil drenching and trunk injection, these are not feasible due to the nature of the site and species. This project consists of a series of ex situ experiments trialing bark painting of phosphonate together with a penetrating surfactant on young and mature trees. Experiments on mature trees also involve the establishment of a bioassay for the disease.