The downside of good growing conditions
Australia’s viticulture industry has a worryingly low awareness about the extent of fungicide resistance in crops, says Syngenta researcher Dr Leanne Forsyth, leaving the industry at serious risk.
Leanne has spent 20 years as an agricultural researcher and academic, with the last five dedicated to developing new solutions for growers as Syngenta’s Technical Manager for Fungicides.
Over that time, Leanne says, despite new and cutting-edge product solutions from companies like Syngenta, Australia’s excellent growing conditions mean fungicide issues remains a serious concern in Australia, more so than in other international viticulture regions.
“In general, many or our viticulture regions in Australia don’t see a lot of rain during the growing season or at harvest from February through to April, so we don’t have as high disease pressure over the season like other regions do, such as in Europe or New Zealand.
“Due to the wide range of export wine markets we have, Australian growers are restricted with some of the fungicide options they have available for use after flowering.
“This means that we don’t have a lot of different fungicide options available to use. And not being able to rotate between different botrytis fungicide groups as readily means diseases here in Australia can potentially build resistance quite quickly.”
With Powdery Mildew and Botrytis still the two biggest disease threats affecting Australian viticulture crops, Leanne says the lack of awareness among growers about the increasing prevalence of fungicide resistance could contribute to the problem.
Recent blind tests run by the National Resistance Monitoring Program that were supported by Syngenta, showed an increase in fungicide resistance across the country.
“There was evidence of resistance for all major fungicides found in those tests,” says Leanne.
“The situation is not resulting in field failure, which is good. But the problem is not going to go away very easily and we need to address it while we can.
“Misuse is one of the big contributors to fungicide resistance. So we need growers to be more aware of the issue and take steps to combat it,” she says.
The fastest and easiest way growers can become part of the ongoing fungicide solution is by taking care to apply any product correctly, in accordance with label instructions, says Leanne.
“Applying any crop protection product as per the instructions means you are getting the right amount, correct spray interval, timing and the right coverage” she says.
If growers do suspect fungicide resistance in their crops, Leanne says it’s important growers take further action to assess the situation.
“If the product has been applied according to the instructions on the label and does not perform, then questions need to be asked about resistance,” she says.
“Follow-up tests are recommended by sending samples to the laboratory to work out what type of resistance there might be, which will determine what follow-up controls are required.
“Syngenta really does lead the world in terms of solutions. Once the resistance has been confirmed, we can assist growers with creating new strategies to deal with that specific issue and the future control of disease.”