FHB Alert Blog

FHB Update from US, 08/15/19

The 2019 wheat growing season is complete and the Fusarium Head Blight Prediction Center stopped updating the disease risk maps. Service will resume in Feb-March of 2020. The 2019 risk maps will be available until the system is reset for the new growing season.

--Erick DeWolf, Extension Plant Pathologist, Kansas State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from US, 08/03/19

The 2019 wheat growing season is nearly over and the Fusarium Head Blight Prediction Center will stop updating the risk maps during the week of August 12th. The 2019 risk maps are available until Feb of 2020 when the system will be reset for the new growing season.

--Erick DeWolf, Extension Plant Pathologist, Kansas State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from MN, 07/26/19

Small Grains Disease Update 07/26/2019

This will likely be the last small grains disease update for the 2019 cropping season. If you have not already done so, I encourage you to really evaluate the extent of the FHB infections in your fields. This is an important first step to not become aware of the extent of the damages but also to start developing a plan of attack to minimize the impact of these FHB infections on the grain and possibly the straw you will market.

Your first step is to maintain quality and avoid the potential discounts due to low test weight, fusarium damaged kernels and the presence of DON is to segregate the worst affected fields or areas of fields and not co-mingle the grain. Your second step is to increase the fan speed during harvest to reduce the number of fusarium damaged kernels in the grain tank. Unfortunately, you will also increase your harvest losses as you increase your fan speed as smaller but otherwise sound kernels will also be left in the field. Often these smaller kernels come from the spikelets above the initial point of infection and where the FHB has grown into to rachis, thereby halting the grain fill of the kernels higher on the rachis.

If needed, the next step is to use a grain cleaner to further reduce the number of fusarium damaged kernels. A Kwik-Kleen grain cleaner or equivalent allows you to clean the grain prior to putting the grain in storage.

Good luck and stay safe with harvest!

--Jochum Wiersma, Extension Agronomist, University of Minnesota Crookston

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from MN, 07/19/19

Since the Fourth of July holiday temperatures and dew points have been unpleasantly high for small grains. Needless to say, the risk models for FHB have been high for all of Minnesota as the Northern Red River Valley has also received some much-needed rain since my last report two weeks ago.

I have been busy with field days and plot tours across the northern half of the state and scoring diseases in the rye and winter wheat trials in the southern locations. It wasn't difficult to find FHB in the southern trials and even in some of the northern trials the first few FHB infections could be found.

The first symptoms of FHB take about 7 to 10 days to develop. This week, therefore, is a good time to start accessing how much damage FHB may inflict this year as a lot the spring wheat across the state headed between the 4th and 10th of July.

These early FHB infections have the most impact on grain yield. First, the affected florets and spikelet will produce the tell-tale, chalky-white tombstone kernels. Secondly, these early infections have the best chance to grow into the rachis is cut off the nutrient flow to the developing kernels in the florets and spikelets above the initially infected floret, thereby halting grain fill.

One key difference between varieties that are rated very susceptible to FHB and those that are rated moderately resistant, is their ability to slow the disease development into to rachis and cutting off the development of the grain above the initial infection.

And although FHB is really a monocyclic disease, i.e. the current infections will not produce spore that will infect the current crop, the crop remains susceptible until you have the crop in the bin. The spores will come from the same sources of inoculum that provided the ascospores for these first infections. The yield losses of these later infections, however, are much less dramatic and the concern is more the presence of DON in the grain.

Finally, these high temperatures and dew points are already taking their toll on the yield potential of this crop. Especially the high nighttime temperatures shorten the grain fill period, resulting in fewer kernels and lower kernel weight.

--Jochum Wiersma, Extension Agronomist, University of Minnesota Crookston

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from SD, 07/17/19

Spring wheat is mostly done flowering but for some of the fields that were planted late and are yet to reach flowering, these are still at risk for Fusarium head blight (FHB/Scab) to develop. The FHB prediction tool is showing moderate to high risk for FHB to develop for the northern half and the southeastern parts of the state. These fields should be protected from FHB by applying a fungicide when 50% of the plants are at flowering. The risk for FHB decreases with time after flowering. Some of the fungicides effective against scab include Caramba, Miravis Ace, Proline, and Prosaro.

--Emmanuel Byamukama, Extension Plant Pathologist , South Dakota State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from ND, 07/13/19

Rain and prolonged periods of high humidity have sustained moderate to high scab risk for susceptible and moderately susceptible varieties. There are a few pockets of moderate to high risk for moderately resistant varieties as well. For wheat that is flowering (or will be flowering soon) in moderate to high risk areas, protect fields with an effective fungicide. As a reminder, research suggests the most amount of FHB and DON suppression occurs when a fungicide is applied at early-flowering or within seven days of early-flowering initiation (seven day application window).

--Andrew Friskop, Cereal Extension Pathologist, NDSU Department of Plant Pathology

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from US, 07/09/19

The focus of the forecasting effort is now on spring wheat in North Dakota and Northern Minnesota. The risk map is currently showing areas of moderate and high risk in these areas of the country. Growers in these areas should consult with local university extension and other advisors to further evaluate the risk of disease and need for fungicide treatment. Selecting the state of interest from the menu to the left of the map will zoom to show more detail and display commentary from local disease specialists. Much of the winter wheat in the southern US has already been harvested. These areas are now excluded from the analysis and displayed as gray areas on the risk maps.

--Erick DeWolf, Extension Plant Pathologist, Kansas State University

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from MN, 07/08/19

Small Grains Disease Update 07/03/2019

The risk assessment models for FHB continues to show a near continuous high risk for FHB in all of Minnesota but the northern half of Polk County and the counties of Marshall and Kittson and the eastern beach ridge of the Red River Valley between Thief River Falls and Fergus Falls. Like last week's update - much of the difference in risk can be explained by overall drier conditions in those areas.

Aphids, meanwhile, have reached the Canadian border. Scout later seeded spring wheat for aphids and treat fields if the threshold of 80% of the stems having one or more aphids is exceeded prior to heading.

Because of the aforementioned drier conditions in Polk, Marshall, and Kittson counties, grasshopper counts are also on the rise. The threshold to treat field margins is 30 nymphs or 20 adults per square yard. Check not just the field perimeter if the wheat was no-till seeded into standing soybean stubble. A threshold of 8 to 14 adults per square yard is used inside the field to start control.

I also found some armyworm larvae in my yard that were quite happy and growing. Check headlands and lodged areas in the field for feeding damage first and treat when 5 or more larvae are present per square foot. If the migrations were smaller and localized, you, again, may only need to treat field margins rather than whole fields.

Finally, this hot, humid weather is pushing the development of the wheat. Having some cooler night not only would lower the risk of FHB but also greatly help preserve the yield potential of this year's crop.

--Jochum Wiersma, Extension Agronomist, University of Minnesota Crookston

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from ND, 07/08/19

There is a high risk for scab for susceptible spring wheat varieties in several areas across North Dakota. In addition to elevated scab risk levels in northwest and southeast ND, new pockets of elevated scab risk formed in east central and southwest ND. Over the past couple days, several acres of wheat received a fungicide and it is likely more acres will be sprayed with a fungicide this week. If a moderately resistant variety was sown, scab risk f is moderate to high for a pocket in southeast and southwest North Dakota. Rain and high humidity this week (in the forecast) will likely maintain a moderate to high risk for the most problematic areas.

--Andrew Friskop, Cereal Extension Pathologist, NDSU Department of Plant Pathology

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

FHB Update from MN, 07/03/19

Small Grains Disease Update 07/03/2019

The risk assessment models for FHB is, as was expected, trending higher in the first part of this week, with many parts of the state showing a near continuous high risk for FHB. The only exception being the northern half of Polk County and the counties of Marshall and Kittson. I'm sure the lack of any measurable precipitation since the middle of May is the cause of this lower risk for that part of the State

The hot, humid weather is pushing the development of the wheat. I suspect that many of you will be spending the coming days, including tomorrow's holiday, either scouting fields to determine when to spray or in a tractor making an application at Feekes 10.51.

Consult NDSU's Extension bulletin 'Ground Application of Fungicides for Suppression of Fusarium Head Blight in Small Grains' (https://www.ag.ndsu.edu/publications/crops/ground-application-of-fungici...) to set up your sprayer correctly and get the most benefit of your fungicide application.

Prosaro, Caramba, or Miravis Ace applied at Feekes 10.51 (beginning of anthesis) will provide the best suppression of FHB. Tebuconazole will provide slightly less suppression of FHB. All products mentioned will give very good to excellent control of leaf diseases for the remainder of the season.

--Jochum Wiersma, Extension Agronomist, University of Minnesota Crookston

For more details, go to the FHB Risk assessment tool at http://www.wheatscab.psu.edu

For the latest news and updates from the U.S. Wheat & Barley Scab Initiative, go to https://www.scabusa.org

Pages

Subscribe to RSS - blogs