Wimmera Wheat Farmers on Lookout for Fungus
Wimmera wheat farmers are being warned to lookout for a fungus which potentially could strip half their wheat yields.
Wheat crops in the Wimmera have already experienced cases of Septoria tritici blotch, with Agriculture Victoria cereal pathologist from Horsham, Dr Grant Hollaway, urging growers to inspect their crops. “Septoria was common in the Wimmera in low levels last year and this has provided the carryover of inoculum for this year,” Dr Hollaway said. “Given repeated wet conditions which are favourable for the disease, septoria can cause losses greater than 50 per cent.” Dr Hollaway said growers should look for symptoms on older leaves, including pale grey to dark brown lesions which contain black fruiting bodies.
Fungicide control is an effective treatment if septoria is found. The Grains Research and Development Corporation has found long periods of leaf moisture are required for disease development, meaning early sown crops and crops sown into wheat stubbles are at most risk.
However, the disease also has an early airborne component, and all wheat crops should be scouted for symptoms. To manage septoria growers should be spraying at early stem elongation (growth stage 31-32) and follow up with a second application at flag leaf (growth stage 39) if necessary.
Dr Hollaway said the timing of fungicide application and choice of fungicide are both important in managing this disease “Because of increasing levels of resistance to fungicides in the Septoria tritici blotch population in Victoria, it is important that the same active ingredient is not used more than once in any season. “Where possible apply fungicides that contain a mix of actives. Growers are reminded to always read the chemical label and only use as directed," he said. More information on the fungus can be found online.
Image source - Agriculture Victoria