A new app to help mungbean growers across Queensland and New South Wales better manage the problematic disease powdery mildew has been launched at the Australasian Plant Pathology Society Conference 2019 in Melbourne on November 28.

Powdery mildew has been an issue since production started and all cultivars currently available are susceptible to the disease, which is estimated to cause up to 40 per cent yield loss in conducive seasons.

While fungicide sprays are still effective and resistance has yet to be detected, preserving current chemistries through best practice is key to effective long-term management of the disease.

The new PowderyMildewMBM (mungbean management) app is designed to assist mungbean growers make more informed decisions about fungicide application to ensure effective management that optimises yields and minimises costs.

Developed in a collaboration led by the Department of Primary Industries and Regional Development, Western Australia (DPIRD) with contributions from the University of Southern Queensland's Centre for Crop Health and Queensland Department of Agriculture and Fisheries (DAF) and co-investment from the Grains Research and Development Corporation (GRDC), the app is suitable for mungbean growers across the northern region.

DPIRD Principal Research Scientist Dr Art Diggle said the app was designed for use during the growing season to assist crucial treatment decisions using evidence-based information to estimate the likely returns from spraying for powdery mildew for individual paddock scenarios.

"The app is simple to use and easy to navigate, requiring the user to input individual paddock data, as well as expected weather conditions," Dr Diggle said.

"It then uses a forecasting model to generate the predicted return from a fungicide treatment, in dollars per hectare, highlighting the probability of a negative or positive return.

"The user can select from several alternative views of the predicted results to suit themselves, including tables and graphs."

Powdery mildew can lead to significant yield loss in conducive weather conditions, with cool and humid conditions favouring the disease.

The PowderyMildewMBM app will help mungbean growers to make decisions on managing this disease in an economically feasible way. - GRDC Senior Crop Protection Manager Dr Emma Colson

GRDC Senior Crop Protection Manager Dr Emma Colson said managing powdery mildew at the right time, with the right control techniques, would substantially reduce costs associated with the disease, and therefore increase farm income.

"The PowderyMildewMBM app will help mungbean growers to make decisions on managing this disease in an economically feasible way," Dr Colson said.

"Resistance to fungicides is developing in plant pathogens, and although it is not yet a problem in mungbeans, we need to be aware of it and manage fungicide use accordingly."

University of Southern Queensland (USQ) Associate Professor Adam Sparks, who contributed research data to the development of the app and helped validate it, agree it could be an important tool in preserving the efficacy of existing chemistries.

"The tool could help growers cut back on unnecessary spraying to keep resistance at bay and improve on-farm profits," he said.

Dr Diggle said the PowderyMildewMBM app would give mungbean growers and consultants more confidence in decisions about whether to invest in spraying for this problematic disease.

"It is intended that the app be continually updated to reflect new experimental results as they become available," he said.

"A semi-quantitative approach has been used for calibration, which recognises the fact that powdery mildew management decisions must be made, and are highly influenced by seasonal conditions, which vary from year-to-year."

The app is a part of the DPIRD and GRDC's collaborative Crop Management series, which also includes the BlacklegCM app and the SclerotiniaCM app, designed to help identify the most effective and profitable disease management strategies for canola growers. It will also soon include the StripeRustWM app for managing stripe rust in wheat, to be launched early in the new year.

The PowderyMildewMBM app, which is suitable for Apple and Android tablets, is available for free from the Apple App Store and Google Play. For more details about the apps visit https://www.agric.wa.gov.au and search crop disease apps.

GRDC Project Code: DAW1810-007RTX