Fusarium won't be spreading south

GrainCorp has opened a Fed 3 wheat segregation for wheat with a high number of white grains because of the disease, which causes toxicity in the grain, and farmers are concerned there will be a further spread following the latest bout of rain.

However, a plant pathologist with the NSW Department of Primary Industries (DPI) has told growers that they will either have the diseases or not by now.

“Fusarium head blight is a consequence of rain and humidity at plant flowering time,” Steven Simpfendorfer said.

“It’s got to be above 80pc humidity in the period from flowering through to the soft dough stage,” Dr Simpfendorfer said.

“If the disease hits earlier in this period, we will see seed loss, and if it hits later, it is more likely to be shown up through infected seed.”

Dr Simpfendorfer, who is based at Tamworth, on the Liverpool Plains, said the worst hit areas were Queensland and northern NSW.

“Queensland in particular had problems, because it got all that rain at a time suitable for the disease.”

He did not think there would be a spread further south, as the conditions were not suitable for the disease at flowering in southern NSW or Victoria.

“Hypothetically, the disease can spread to southern cropping zones, however, once the crop is past the soft dough stage there is no chance of further infection.

Dr Simpfendorfer said varietal issues also had an impact on how severe the disease was, saying durum wheats were far more susceptible than other varieties.

Although the disease has been damaging for some growers, he said other issues such as sprouting, fungal staining and general weather mottling would be bigger problems this year.

He said light test weight and low vigour grain could also present farmers with a problem at sowing time next year.

“You’ve got to ensure you’ve got good quality seed.”