Disease Update 4/4/2016

Recent cold weather and increasingly dry conditions across Kansas and Oklahoma have slowed wheat progress but wheat is still two to three weeks ahead of normal.  Reports out of Oklahoma have wheat ranging from flag leaf emerging to heads emerging.  Kansas has wheat just starting to joint in the northern part of the state to flag leaf emerging in the southeast.  Freeze damage, outside of leaf burning, was not as severe as first feared for most of the area but some fields did receive damage to the growing point/developing head.  I would advise to continue to scout your wheat for freeze damage as temperatures continue on their spring roller coaster,

Stripe rust has continued to slowly spread across Kansas and Oklahoma with the disease being found up to the Nebraska border in central KS.  Stripe rust has also been found northeast of Denver, CO in the Prospect Valley area.  For the most part, stripe rust is at low levels and only found on the lower leaves, however, a few reports out of Oklahoma and southeast KS have stripe rust at moderate to severe levels and moving up in the canopy.  A lack of moisture has slowed the progress of stripe rust overall but it can rapidly spread if favorably moisture returns.  Producers should continue to monitor their fields and strongly consider a fungicide at flag leaf unless you are already seeing moderate to severe levels or moisture returns in which an earlier application of fungicide may be warranted.

Leaf rust is present in western KS and, more than likely, eastern CO.  It also has been found in south central NE.  All these reports have leaf rust at low levels and not of a concern to producers right now.  Powdery mildew is present in quite a few fields in Kansas with some having severe infection in central and eastern KS.  Septoria blotch and tan spot can also be found but once again not many fields with too severe of infections.

KState Agronomy EUpdate Stripe Rust Distribution

Figure 1 Stripe rust distribution in Kansas. Credit: K-State eUpdate posted April 1, 2016.

 

Stripe rust Republic County, KS

Figure 2 Stripe rust found in Republic County, KS. Credit: Bryson Haverkamp

 

Tan spot Washington County, KS

Figure 3 Tan Spot found in Washington County, KS. Credit: Bryson Haverkamp

 

Septoria tritici blotch Republic County, KS

Figure 4 Septoria tritici blotch found in Republic County, KS. Credit: Bryson Haverkamp

By Bryson Haverkamp

By |April 4th, 2016|News Alert|Comments Off on Disease Update 4/4/2016

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