VG07070 Conference Notes 2008

This project was formed by Government agencies, private industry, universities and international researchers, to benchmark disease predictive models for major vegetable crops.

There is scope to increase the profitability of these crops and reduce pesticide inputs while maintaining product quality.

The concept was developed by the Pathology GAP Analysis Project VG06092.

Liz Minchinton
Victor Galea
Des Auer
Joanna Petkowski
Rob Faggian
Barbara Hall
Ian McCauley
Hoong Pung

Chrys Akem

Roy Kennedy & Alison Wakeham UK

VG07070 - Benchmarking predictive models, nutrients and irrigation for management of downy and powdery mildews and white blister - Conference Nov 2008
Download 190kb

Progress report :

Irrigation :

Over-head irrigating broccoli at 4.00 am compared to 8.00 pm reduced white blister incidence on broccoli heads by 50% and increased farm profits by 5%.

Growing a tolerant broccoli variety reduced white blister incidence by 96% and increased farm profits by 22%.

White Blister :

The Brassicaspot disease predictive model for white blister was evaluated on Chinese cabbage in Victoria and on broccoli in Victoria and Tasmania.

On Chinese cabbage, the model recommended a spray 14 days before harvest, and co-incidentally, this was the best time phenologically to protect the wrap leaves and hearts.

In four of five broccoli trials, the Brassicaspot disease predictive model, weekly and consultant spray programs provided the same level of control of white blister on broccoli heads.

Model-based spray programs saved 5, 10, 11 or 13 weekly spray applications in different trials, but program efficacy was lower when a spray was not applied at button stage.

Apparently for good control, model-based programs should include a spray at button stage if no spray is predicted.

Horticulture Research International UK has produced antibodies to white blister spores as the first step in developing a real time spore trap test kit to enhance the Brassicaspot disease predictive model.

Downy mildew :

DPI Vic is evaluating downy mildew disease predictive models for lettuce and the initial trial has reduced one fungicide application.

Research on model improvements is continuing with field trials, the collection of microclimate data, and trap plant, spore trapping and growth chamber studies.

Powdery mildew :

A powdery mildew predictive model for cucurbits is being developed by UQ and QPIF.

The PhD student on the project has reviewed the literature and commenced growth chamber studies to determine the primary factors associated with infection.

Nutrients :

The effect of nutrients (N) on the susceptibility of Brassica plants to white blister is under evaluation by SARDI.

Acknowledgments :

Funding was provided by Australian vegetable growers (through the R & D levy) and the Department of Primary Industries, Victoria. The Australian Government provides matched funding for all HAL’s R&D activities.

^ Back to top