Samples of stubble from last year’s canola crops are being sought from growers and advisers in the southern and western cropping regions to assist with research into fungicide tolerance in blackleg fungal strains.
Following the identification of blackleg isolates with tolerance to the fungicide fluquinconazole during a limited survey in 2014, further survey work is being undertaken to determine the distribution of the fungicide tolerant fungal strains, potential yield losses and how the tolerance may affect other fungicides.
With the support of the Grains Research and Development Corporation (GRDC), the National Canola Pathology Program will be surveying canola paddocks for fungicide tolerance in 2015.
As part of the survey, canola disease expert Steve Marcroft is seeking 2014 canola stubble samples from growers and advisers.
“We want to screen at least 200 2014 stubble samples from a wide range of regions,” Dr Marcroft said.
“To provide a sample for screening, growers are asked to simply collect 20 canola stalks from their 2014 crop, and record the cultivar name and fungicides used on the canola crop last year.
“We are happy to also screen stubble from crops that had no fungicide applied.
“Provision of paddock GPS is preferable but growers can just indicate the closest town for confidentiality purposes, if preferred.”
Growers and advisers willing to provide stubble samples are asked to email Dr Marcroft via BlacklegMGP@gmail.com who will then provide a sampling protocol via email.
“We will screen the stubble samples and send the individual grower their result by the end of 2015 or earlier if possible. All data will be confidential and no names or farms will be reported.” There are no quarantine issues with fungicide tolerance.
In the meantime, Dr Marcroft recommends that growers continue using fluquinconazole in 2015.
“However, other blackleg management practices such as cultivar blackleg rating, separating crops from last year’s stubble and rotation of cultivar resistance groups should be given a higher priority,” Dr Marcroft said.
Blackleg, a sexually reproducing pathogen, can cause severe yield loss in canola crops, but can be successfully managed through an integrated approach.
Steve Marcroft, Marcroft Grains Pathology
03 5381 2294
Sharon Watt, Porter Novelli
GRDC Project Code
UM00051, MGP0003, DAN00177