CropWorld 2010: Earlier spray may be needed for FEB control
FUNGICIDE sprays for control of fusarium ear blight may need to be applied earlier than is currently the case in order to obtain good disease control and limit production of mycotoxins.
That is according to Rothamsted Research PhD student Neil Brown, who told the CropWorld conference that during his research he had identified a substantial phase of deep, symptom-less FEB infection, which could occur within five days of infection taking place during the wheat flowering phase. During this phase infected tissue would appear healthy, with disease symptoms only occurring when host cells died and FEB hyphae penetrated the cell to scavenge remaining nutrition.
“This symptom-less infection has a profound effect on our crop protection mechanisms, as we evaluate our resistant wheat lines and evaluate the efficacy of our fungicides based on disease symptoms,” he said.
The existence of a phase of symptom-less infection may explain the poor correlation between visible disease symptoms and mycotoxin contamination, said Mr Brown.
Current and new fungicides needed to be screened for their effect on reducing symptomless infection, he added. Fungicides probably needed to be applied earlier, perhaps as a pre-anthesis spray to prevent the establishment of this deep infection.
Mr Brown’s research had also revealed that production of mycotoxins linked to FEB infections was higher where there was symptom-less FEB infection.
The next stage of research was to identify the drivers of symptom-less infection, which might help in targeting fungicides.
- Symptom-less infection of FEB spreads rapidly through the plant
- Mycotoxin production is higher in symptom-less infections
- Application of fungicides needs to be before the appearance of disease symptoms
- A reliable FEB forecasting and monitoring system is required