Tag: wheat

Late Season Fungicide Applications in Wheat

Nathan M. Kleczewski Ph.D., Extension Plant Pathologist, University of Delaware

I have had some questions regarding fungicides and application timings in wheat approaching flowering.   In particular, the question of efficacy on canopy and head diseases has come up in conversations.  The first thing to note is that the fungicides that are recommended for Fusarium Head Blight (FHB) suppression (Caramba, Prosaro, Proline) are effective in controlling foliar diseases.  Commonly encountered foliar diseases include Stagonospora leaf blotch, tan spot, powdery mildew, and the rusts.  However, it is important to understand that although these products are labeled for FHB, they are only effective if applied at the correct timing.  Applying these products before flowering will not result in FHB suppression.  This is because the FHB pathogen infects flowering grain heads (Figure 1). Continue reading Late Season Fungicide Applications in Wheat

Know Your Rusts

Nathan Kleczewski, Extension Pathologist, University of Delaware

Stripe Rust is active in the Eastern shore of Virginia on susceptible wheat varieties.  Last week I wrote an article on management recommendations and scouting information on the Field Crop Disease Management blog (hyperlink to article).  Understanding your resistance rating to stripe rust is key in determining if this disease should be a concern for you if it moves into the area and temperatures remain cool and humid (below 70 F during the day, and 60F during the night).  Check your seed catalogues or contact your dealers for ratings to stripe rust.  Those growers planting varieties with very good to excellent resistance should not need to worry about additional fungicide applications.  Those with susceptible varieties need to pay close attention to their fields and reports of the disease, and consider a fungicide application if the disease is detected nearby or in the field.  Yield loss is related to the growth stage of the plant relative to arrival of the pathogen.  Plants infected earlier in growth (prior to heading) may suffer significant losses under appropriate conditions.

Several people have asked about if leaf rust and stripe rust ratings are the same. No they are not.

Stripe rust on wheat.  Notice the bright orange “pustules” that are arranged in long strips. 

Resistance to these diseases is controlled by different genes and therefore a variety with excellent leaf rust resistance may not be resistant to stripe rust.  Ratings for many stripe rust varieties in the region can be found at the Field Crops Plant Pathology website under the heading “Small Grains” as well as the Virginia Tech Small Grains Variety Trials webpage.

Options for Freeze Damaged Wheat

Greg Halich, Extension Economist, University of Kentucky

 

A severe freeze in mid-March has likely damaged much of the wheat crop in Kentucky. The extent and severity of the damage will be better known one to two weeks after the freeze when baseline estimates can be made. Normally, producers would have three options to deal with wheat stands that have been damaged at this stage:
1) Stay the course, harvest the wheat and then double-crop soybeans.
2) Terminate the wheat stand and plant corn.
3) Terminate the wheat stand and plant full-season

Read the rest of the article on the University of Kentucky Grain Crops Blog:

https://graincrops.blogspot.com/2017/03/options-for-freeze-damaged-wheat-which.html