May 23, 2008

In South Central And Eastern Nebraska

Fig. 1. Risk of Fusarium head blight (scab) in Nebraska as of May 30, 2008. Source: http://www.wheatscab.psu.edu/riskTool.html (Links to larger version)

With the recent rainfall and with wheat flowering approaching, the risk of Fusarium head blight (scab) of wheat has increased in south central and eastern Nebraska. Models from the Fusarium Head Blight Prediction Center Web site show moderate to high risk (Figure 1). More rainfall is forecast for next week, which may further increase the risk.

At this time the strategy for managing FHB is to apply an appropriate fungicide at early flowering. The optimum timing for fungicide application is at 15% flowering. Fungicides registered for suppression of fusarium head blight include Folicur (4 fl oz/ac), Proline (4.3 to 5.7 fl oz/ac), Caramba (14 to 17 fl oz/ac), and Tilt (4 fl oz/ac). A tank mixture of Folicur (3 fl oz/ac) and Proline (3 fl oz/ac) also can be applied at early flowering to suppress this disease.

In addition to suppressing fusarium, Folicur also can control rust diseases; Proline and Caramba can control rust diseases and several leaf spots including Septoria leaf and glume blotch and tan spot; and Tilt can control powdery mildew, rust diseases and leaf spots.

Stephen Wegulo
Extension Plant Pathologist