WA canola growers, particularly where crops have established in parts of the southern region, have been cautioned against the threat of blackleg, with recent conditions potentially creating a “perfect storm’’ for the disease in some areas.
Blackleg disease models from the Department of Primary Industries and Regional Development suggest spore showers are occurring in some areas, coinciding with canola crops at the seedling or early leafy stages, which enhances the risk of disease infection.
Plants are at greater risk of severe infection and death up until the six-leaf stage.
Bayer Southern WA customer advisory representative Craig White said the delayed start to the season and cold conditions had resulted in small crops at this stage, and they could be hit by blackleg infection.
Mr White urged growers to take a close look at the disease ratings of the canola varieties grown and their crop rotation risk, then assess whether a foliar fungicide application was required.
The recently-released Aviator Xpro foliar fungicide, from Bayer, has shown to be a strong option for blackleg disease.
It contains bixafen, a novel member of the Group 7 fungicides, which also offers an alternate mode of action for resistance management, as well as the proven performance of prothioconazole.
Recent WA trials showed the highest levels of blackleg control were achieved following foliar application of Aviator Xpro, in combination with an effective blackleg seed treatment or in-furrow flutriafol application.
“This multiple fungicide application strategy really paid off under high blackleg pressure. Aviator Xpro extended the disease protection and reduced blackleg infection, helping to maximise yield,” Mr White said.
In addition to blackleg and sclerotinia in canola, and ascochyta blight in chickpeas, this season Aviator Xpro has been approved for aerial application and has additional registrations across cereals (wheat and barley) and pulses (faba beans, field peas and lentils), including blackspot in field peas.