Entomopathogens for management of key pests of tea tree oil


Pyrgo beetle (Paropsisterna tigrina) is one of the most serious insect pests of Tea Tree (Melaleuca alternifolia) causing yield losses as high as 80% (equating to income losses of $6,4009,600 per ha)1. Pyrgo beetle in Tea Tree is currently managed by application of chemical pesticides. Continuous use of one insecticide has already led to resistance issues in Pyrgo and other insect pests. Chemical use can also affect product perception and market access. The entomopathogenic (=causing fatal disease in insects) fungus Beauvaria occurs naturally in Tea Tree and is fatal not only to Pyrgo beetle but also to other insect pests including Noctuids, Leaf hoppers, Faex beetles, Scarab beetles and wasps (Fig. 1). It is likely that Beauvaria will also affect other pests of Tea Tree including Lepidoptera, Psyllids, mites, midges and other Chrysomelid beetles. Beauvaria has been successfully developed to manage Sigastus weevil in macadamia. This project will evaluate the potential for endemic Beauvaria isolates collected from insects on Tea Tree to control Pyrgo beetle. Laboratory trials will confirm efficacy of Beauvaria isolates, environmental conditions that favour Beauvaria and sensitivity of the isolates to fungicides used in Tea Tree. Trials will be conducted to evaluate efficacy under field conditions. Comparative efficacy data will be generated for locally isolated Beauvaria and commercially available products.


Tea Tree Oil

Research Organisation

(DPI) The Crown in right of the State of New South Wales acting through the Department of Primary Industries within Regional NSW

Objective Summary

To build on earlier research investments in IPDM in Tea Tree industry this project will: 1. Confirm that the Beauvaria fungus isolated from tea tree effectively to kills Pyrgo beetles 2. Compare locally isolated fungi with commercially available preparations under laboratory and field conditions 3. Evaluate the timing and method of application (spring versus winter) The expected outcomes of the project are: 1. Identification of Beauvaria isolates from tea tree or commercial preparations that most effectively kill Pyrgo beetle 2. Understanding of environmental conditions that favour infection of Pyrgo beetle by Beauvaria 3. Understanding of the potential to protect tea trees against Pyrgo beetle by inoculating with endemic Beauvaria compared with commercially available formulations.

Project Code


Project Stage


Project Start Date

Tuesday, May 7, 2019

Project Completion Date

Tuesday, May 31, 2022

Journal Articles From Project

Not Available

National Priority

An environmentally sustainable Australia

National Priority

Adoption of R&D

National Priority

TTO-Improving supply