Southern corn rust has appeared at least 2 weeks earlier in 2014 (5 June) than it did in 2009, 2010, 2011, 2012 or 2013. Appearing earlier means that this disease will likely be more problematic in 2014 than in recent years.
Corn that is approaching (or has passed) the tassel growth stage is worth protecting if the yield potential is there. It’s generally recommended to wait to spray for southern rust until your crop is approaching tassel.
Triazole fungicides (like tebuconazole) are effective against rust (but lack the broader activity against northern corn leaf blight) and have a two week protective window. Strobilurin products and combination strobilurin/triazole of strobilurin/SDHI (Priaxor) have 3 week protective intervals and also a broader spectrum of activity.
