Victorian growers urged to keep paddocks ‘Free for February’ to control green bridge rust disease threat
Victorian growers are being urged to keep paddocks ‘Free for February’ to minimise the risk of rust and other diseasessuch as powdery mildew, and pests such as mites or aphids, surviving on a green bridge.
Agriculture Victoria’s Senior Plant Pathologist, Dr Grant Hollaway 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 Hollaway 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 Hollaway 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 Victoria in 2016, leaf rust in both barley and wheat and wheat stripe rust were widespread across the state. There were also late reports of stem rust. With the frequent summer rain, these diseases will be increasing on cereals growing as volunteers.
“With a combination of high levels of the pathogen and most common wheat varieties having some degree of susceptibility, there is certainly a likelihood of leaf rust carrying over to 2017 on cereals growing as volunteers following the summer rain,” Dr Hollaway says.
Senior Plant Pathologist, Cereals
Grains Innovation Park
110 Natimuk Rd, Horsham 3400