NSW growers urged to keep paddocks ‘Free for February’ to control green bridge rust disease threat
New South Wales growers are being urged to keep paddocks ‘Free for February’ to minimise the risk of rust and other diseases such as powdery mildew, and pests such as mites or aphids, surviving on a green bridge.
New South Wales Department of Primary Industries Senior Plant Pathologist, Dr Andrew Milgate says that while a longer break without weeds would provide improved control and potential yield benefits, if all growers kept paddocks bare for February as a minimum, the risk of rusts and other disease and pest threats would be significantly reduced.
“It is critical that growers eradicate the green bridge as rust pathogens rely on green leaf material to survive and pass onto crops in the following season,” Dr Milgate says.
“Growers must be vigilant and look for rust-susceptible weeds and crop volunteers not only in paddocks, but along fence lines, around sheds and silos. At least a month of no green growth is required to prevent disease survival.”
Dr Milgate suggests growers adopt the target of Free for February and encourage other growers to do the same.
“The reason the month of February is key is that some regions are still harvesting in January, and some growers want early feed in March, so February is the best chance for a full pest and disease break,” he says.
In NSW in 2016, leaf rust in both barley and wheat and wheat stripe rust were widespread across the state. The low rainfall over much of the state in the past month provides an opportunity to achieve widespread green bridge control and to target those regions which have had storm activity recently. Diseases will be increasingon cereals growing as volunteers.
Northern: Steve Simpfendorfer
NSW Department of Primary Industries, Tamworth
Southern: Dr Andrew Milgate Research Scientist – Plant PathologyNSW Department of Primary Industries, Wagga Wagga