Growers now have additional options to improve in-crop management of two potentially devastating diseases in their canola crops.
Sclerotina stem rot was widespread in the northern agricultural region in 2011, causing yield losses of 25 per cent in the worst affected crops, while blackleg was prevalent across the south coast of the Great Southern.
Field trials led by Department of Agriculture and Food research officer Ravjit Khangura and co-funded by the Grains Research and Development Corporation, revealed some tangible findings that will help growers refine and potentially improve their fungicide applications this season.
Dr Khangura said the results showed how important the timing of the fungicide applications was to controlling both Sclerotinia stem rot and blackleg.
“Trials in the Chapman Valley using the variety Cobbler found that fungicide application significantly reduced Sclerotina stem rot, with the highest yield (2.85 tonne per hectare) coming from Prosaro®, a new fungicide which is now available on the market to control blackleg,” she said.
“The results showed a foliar application at early flowering stages proved most beneficial.”
This year Dr Khangura plans to investigate the timing of fungicide applications in different environments to minimise Sclerotina stem rot, as well as undertake an economic analysis of control options.
“An initial, basic analysis has already shown that with a 0.4 tonne yield response and a canola price of $500 the benefit is considerable,” she said.
The blackleg trials at Katanning using Telfer canola, which is rated as moderately-susceptible to susceptible for blackleg, also had a significant response to a single foliar application of Prosaro®. The trial is set to be expanded this year to other canola varieties.
“Foliar fungicide applications provide growers, who have not used either seed dressing or an in-furrow treatment at seeding, with another option for in-crop control,” Dr Khangura said.
“This is most effective when used in conjunction with the forecast tool Blackleg Sporacle to determine the best application time.”
Currently, the model is predicting that the release of blackleg spores has already commenced in south coastal and some areas in the Great Southern while spore development is at an advanced stage in most of the central agricultural region.
Growers are urged to carefully asses their overall risk and consider applying foliar fungicide.
Further information can be accessed at the department’s Crop Disease Forecast website at agric.wa.gov.au
Media contacts: Jodie Thomson, media liaison +61 (0)8 9368 3937