Biological management of Fusarium head blight and mycotoxin contamination in wheat

Abstract

Fusarium head blight (FHB), caused by Gibberella zeae is a harmful disease of wheat. To manage FHB and mycotoxin contamination in wheat, field experiments were conducted from 2007 to 2008 to evaluate a total of 20 selected bioagents for their ability to inhibit perithecial production of G. zeae and for the control of FHB and deoxynivalenol (DON) contamination, in comparison with the registered fungicide Folicur (tebuconazole). All 20 bioagents significantly reduced the perithecial production compared to the untreated control. Clonostachy rosea strain ACM941 was the most effective treatment, reducing the production of perithecia by 63.7% in 2007 and 67.5% in 2008. These effects were significantly better than Folicur fungicide, which reduced perithecial production by 30.4% and 20.5%, for 2007 and 2008, respectively. When sprayed on to wheat heads, seven of the 20 bioagents significantly reduced the FHB index, one reduced Fusarium damaged kernels (FDK), and six reduced DON content in grains in 2007. ACM941 was the only treatment that significantly reduced FHB index, FDK, and DON, by 46.4%, 29.0% and 28.7%, respectively. Among the six bioagents and three formulated products evaluated in two separate field trials in 2008, ACM941 and its formulated product ACM941-CU were the only treatments that significantly reduced FHB index, FDK, and DON. The treatments reduced FHB index by 30.8% and 31.4%, FDK by 17.8% and 43.8%, and DON by 30.8% and 37.1%, for ACM941 and ACM941-CU, respectively. These effects were less marked than those of the Folicur fungicide that reduced FHB index by 98.8%, FDK by 94.2%, and DON by 92.1%. Results of this study suggest that ACM941 is a promising bioagent against G. zeae and may be used as a control measure in organic farming and in an integrated FHB and DON management program for wheat production.