With a rust outbreak in Australia having the potential to slash farm incomes, University of Sydney’s Professor Robert Park said growers need to think before they sow this year and consider the implications of managing rust outbreaks in 2013.

He said it was vital to plan a response to rust this year at the start of the season rather than waiting for a rust outbreak to occur.

“We are taking a clear stance and actively encouraging growers to phase out susceptible and very susceptible varieties from their rotation. Varietal selection must be the first line of defence,” Professor Park said.

In 2011, an industry survey found growers make variety selections based on the yield potential of the variety only. They did not factor in disease management costs or the costs of decreased yields following a disease outbreak.

“While yield potential is an obvious and crucial factor to consider, we are urging growers to think beyond only yield because a rust outbreak can slash grain returns by more than half,” he said.

The push for growers to reconsider variety choice stems from the industry risk of a large-scale rust outbreak as well as the risk of mutant rust isolates that can overcome resistance genes that protect many Australian wheat cultivars from rust.

The Australian Cereal Rust Control Program Consultative Committee is also keen to see growers move away from their dependence on chemicals to manage disease outbreaks.

“In the past, many people have relied on fungicide applications. While this remains an effective management tool, growers should be aware that while fungicides may work on leaf and stripe rust, they are less effective on stem rust especially in thick canopies where fungicides may not reach all stems,” Professor Park said.