Background/context:

Members of the genus Phytophthora infect a wide range of commercially valuable plants in tropical and other regions. Seedlings, in particular, are highly susceptible to Phytophthora root rot. Phytophthora incited diseases cause in excess of AUD$300 million per year in Australia in lost production and control measures.

 Aim:

The project aimed to expand the diagnostic capacity of the Phytophthora DNA diagnostic test developed through prior centre research to include important exotic Phytophthora species.

Major Outcomes:

• Provision of identification services to various industries, mainly nursery and horticulture; a total of 1660 samples for Phytophthora identification were processed during the life of the project.

• P. cactorum has been established as the main Phytophthora pathogen on strawberry in Queensland (in collaboration with Mr Don Hutton (DPIQ) The presence of P. cactorum has led to changes in disease management, including obtaining strawberry runners from alternative suppliers, and different chemical treatments before planting runners in the field.

• At least 7 different species of Phytophthora have been identified from olives that showed signs of decline and wilting (in collaboration with Ms Barbara Hall (SARDI). The presence of Phytophthora, and especially a new species of Phytophthora, has resulted in improved nursery practices and more careful selection of planting stock when establishing olive orchards. Treatment of stock with phosphonate and Metalaxyl at planting has been introduced to limit the impact of Phytophthora on young plants.

• Investigation of the cause of bud rot in Areca nut on Guam and the Northern Marianas on behalf of the Secretariat of the Pacific Community, Plant Protection Service.

• Investigation and development of a management plan for potato late blight in PNG on behalf of ACIAR.

• Dr. Drenth has written a monograph on diversity and management of Phytophthora in South East Asia as part of the ACIAR grant in collaboration with Prof. David Guest from the University of Sydney. This book highlights many of the Phytophthora disease problems in tropical crops and contains a large number of colour photographs, which show symptoms of Phytophthora diseases on a large number of tropical crops. This is the first time that information on Phytophthora diseases occurring in tropical regions is collated focussed on disease symptoms in the field. The book aids the identification of Phytophthora problems in the field outlines the disease cycles and provides an in depth overview of available integrated disease management practices.

• A Phytophthora diagnostic kit has been validated and made available commercially through a license agreement with C-Qentec Diagnostics Pty Ltd, the diagnostics arm of BayerCrop Science, in 2004. The decision was made by BayerCrop Science to wind-up C-Qentec in 2006, after which the Phytophthora IDENTIKIT has been made freely available to research organisations in Australia and internationally.

For more information contact:

Dr André Drenth
Department of Primary Industries and Fisheries
Phone: +61 (0)7 3896 9345
Email: Andre.Drenth@dpi.qld.gov.au