Foliar fungicides provide chemical control of Fusarium head blight of wheat in South Africa

Abstract

Chemical control of a yield-limiting, quality-reducing wheat disease like Fusarium head blight (FHB) is an important management strategy; however, no fungicides are registered against it in South Africa. The aim of this study was to determine foliar fungicides and seed treatment efficacy for FHB management. Three commercial fungicides and two seed treatments were evaluated in a naturally infested field during 2011 and 2012. Significant interactions between the seed treatments and the foliar fungicides were obtained for FHB incidence and yield. When the fungicide Abacus® was sprayed in combination with either of the two seed treatments, FHB incidence was significantly decreased compared with use of the fungicide alone. Prosaro® sprayed in combination with Galmano® Plus as a seed treatment significantly decreased yield compared with the use of Prosaro alone or in combination with Vitavax® Plus as a seed treatment. The fungicide treatments significantly reduced FHB incidence and the percentage of Fusarium-damaged kernels (%FDK) when compared with control treatments, and significantly increased the yield. A weak but significant correlation was recorded between deoxynivalenol (DON) and %FDK. Strong negative correlations were observed between hectolitre mass (HLM) and FHB incidence and %FDK, respectively, and between yield and %FDK. These results indicate that the chemical control of FHB of wheat can be used to manage the disease in South Africa. Future research, therefore, must focus on integrating chemical control with host resistance to obtain optimal results.

Keywords:

• field trials
• fungicide combinations
• Fusarium-damaged kernels
• mycotoxins
• seed treatments
• yield increase

Acknowledgements

The Winter Cereal Trust and the Western Cape Department of Agriculture are acknowledged for financial support of the project.