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The wheat scab risk for Baldwin and Mobile Counties is high as compared with the low risk for scab development for the remainder of Alabama.  Kim Wilkins mentioned that she saw some scab in early Baldwin Co. wheat.  Wheat is flowering across Southwest Alabama, so producers should make (or already have made) a fungicide application before the next rain event scheduled for this coming weekend.  Prosaro at 6.5 to 8.2 fl oz/A or Caramba at 10 to 17 fl oz/A are registered for scab control in wheat.  Proline @ 5.0 to 5.7 fl oz/A also is labeled for scab control.  Currently, Prosaro is the most widely used fungicide for scab control in wheat.  Strobilurin fungicides (i.e. azoxystrobin, floxastrobin, picoxystrobin, and pyraclostrobin) when applied to the seed head at flowering can significantly intensify scab in wheat.  


A low level of rust activity along with a low to moderate level of Septoria glume blotch was also noted in Baldwin Co at the Gulf Coast Research and Extension Center.  Disease activity was negligible across the entire wheat variety study as well as in several tiers of wheat at the Brewton Ag. Research Unit in Brewton. 

 

Head extension should just be getting started in North Alabama.  With the exception of trace levels of powdery mildew and Septoria leaf spot, disease activity at two North Alabama locations visited late last week was low on wheat showing the flag leaf but no seed heads.  Producers need to scout fields to determine if there is sufficient Septoria glume blotch, leaf rust, and powdery mildew in their wheat to justify a fungicide application to protect the flag leaf.  Fungicide applications to the seed head for scab control are almost mandatory as grain elevators will not purchase scabby wheat.  Scab fungicide applications will also provide good protection from Septoria diseases on the leaves and head, along with leaf rust, and powdery mildew. 


Last Friday, some cold injury to the flag leaves from the Thursday morning freeze was also noted on some breeding lines and commercial varieties at the Tennessee Valley Research and Extension Center.




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