FHB Alert Blog

FHB Update from SD, 06/10/19

Winter wheat in South Dakota ranges from flag leaf to flowering as of the week of June 10. Wheat that is heading or flowering is most prone to Fusarium head blight (FHB or scab) development provided the weather conditions are conducive, since the source of inoculum is plenty in the environment. Based on the FHB prediction tool, the risk for FHB is currently low in South Dakota with exception of few scattered areas along the Missouri River in Lyman, Brule, Buffalo and Hughes Counties where the risk is mainly moderate. The decision to apply a fungicide to manage FHB should be based on the current risk and also on the weather forecast in the next several days if wheat is at heading or flowering. High humidity or rainfall in the forest can change the risk for FHB from low to high in a short time. If a susceptible or moderately susceptible cultivar was planted, a fungicide is advised for areas in moderate or high risk for FHB. The best fungicide timing for FHB management is at flowering (50% of the plants are flowering). Follow this link for fungicides effective against FHB shorturl.at/hlDU5

--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 MI, 06/06/19

The weather pattern has been quite favorable for Head scab during the past couple weeks so growers are encouraged to consider fungicide use if conditions warrant. Heads and flowers will likely emerge in southern counties during the next week. We may still be a week or more away in the Thumb and north-central counties. We now have three main products from which to choose: Caramba, Miravis Ace and Prosaro. If one elects to treat:: apply a few days after the first flowers emerge; target the heads by raising the boom to 8 to 12 inches above the heads; use dual nozzles directed both forward and backward ( or, if using single nozzle, at least direct it forward to achieve as much spray deposition on heads as possible); and create a moderately fine spray (if a misty vapor is rolling off the boom, the particles are too small and adjustments should be made).

--Martin Nagelkirk, Extension Educator, Michigan 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 NY, 06/04/19

The Fusarium Risk Assessment Map (http://www.wheatscab.psu.edu/riskTool.html) continues to indicate a moderate to high risk of Fusarium head blight (FHB) for several areas of New York. Much of the state’s winter wheat will initiate flowering this week. The triazole products Caramba and Prosaro are the most effective fungicides for suppression of FHB and deoxynivalenol (DON) mycotoxin contamination when applied at flowering (emergence of yellow anthers on heads). A flowering application of triazole fungicide should be based on Fusarium head blight (FHB) risk as well as the risks of powdery mildew, rusts, and fungal leaf blotches in the upper canopy based on scouting of individual fields. There is an application window of approximately 7 days from the beginning of flowering in which reasonable FHB and DON suppression can be expected.

All but the latest planted winter barley is beyond the timing for a fungicide application. In barley, maximal suppression of FHB and grain contamination by DON results when fully emerged heads are sprayed with full label rates of Caramba or Prosaro fungicides. Application up to 7 days after full head emergence may still result in significant suppression of FHB and DON.

Attend Cornell’s Small Grain Management Field Day (http://events.cornell.edu/event/2019_small_grains_management_field_day ) on June 6 to learn more about integrated management of FHB and DON and to view the leading varieties of winter wheat, barley, and rye.

--Gary Bergstrom, Extension Plant Pathologist, Cornell 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, 06/03/19

The focus of the forecasting effort shifts north this week to MI, NY and WI. The risk map is showing some moderate to high risk in these areas today. 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.

--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 OH, 06/03/19

Most of the wheat fields in the northern half of the state reached anthesis last week. The remaining fields will reach this critical growth stage during this week. The risk for Fusarium head blight (FHB) has been moderate-to-high over the last 5-7 days on susceptible varieties planted in the northwest corner of the state. However, persistent rainfall, soggy fields, and difficulties scheduling an aerial application, prevented some fields from being sprayed to control scab and vomitoxin at the anthesis/flowering growth stage. If the risk for scab was high a few days ago when your field reached anthesis, but you were unable to apply a recommended fungicide, you can still make an application up to 6 days after anthesis and see good results in terms of scab and vomitoxin control. This is true for Prosaro, Caramba, and Miravis Ace. Applications made 4-6 days after anthesis are effective against scab and vomitoxin and are particularly useful when the weather following anthesis is consistently favorable for scab. In fact, even if the scab risk had decreased over the last few days, a late application would still be warranted, given that conditions were favorable for scab during the week leading up to anthesis.

--Pierce Paul, Extension Plant Pathologist, Ohio 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 IL, 06/03/19

Much of the wheat has flowered in the S and Central parts of IL. Expect late flowering wheat in the N most parts of IL to flower within the next 7-10 days. Over that period of time additional rains are forecast, which may slightly elevate risk levels. Wheat that flowered approximately 3 weeks ago should be showing symptoms of disease if infections occurred. For more on harvest-based management strategies for FHB go to http://cropdisease.cropsciences.illinois.edu/?p=908

Remember to switch the model to best approximate the resistance level of your varieties. The map defaults to susceptible, but your risk will change substantially if you planted moderately resistant or even moderately susceptible varieties.

--Nathan Kleczewski, Research Assistant Professor and Extension Specialist, University of Illinois

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 PA, 06/03/19

Infection risk remains high and increasing across the west and northern tier of PA this week. Fields in central to northern PA which are now or will be flowering in the next few days should be sprayed to prevent infection and reduce potential toxin production.

--Alyssa Collins, Extension Field Crops Pathologist, Penn 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 OK, 05/31/19

Harvest in southern OK started just this week, so this report will focus primarily on wheat in central, northern, northwestern and the panhandle of Oklahoma. It appears that the wheat crop is well along in its development and needs some dry and warmer weather to finish (as well as to allow harvest!). The primary issues this past week have been deterioration of leaves and head discoloration. The wet environment certainly is contributing to both of these issues. In wheat around Stillwater, heads are being discolored due to black chaff (a bacterial disease) as well as Septoria/Stagonospora that cause leaf spotting as well as head discoloration. There also is a general darkening of heads, called melanism, which results not from a disease but rather is related to genetics and environment. This melanism is difficult to distinguish from the other diseases that are present, especially because this year there seems to be all these happening at once.

Other diseases that are likely to be observed at this point in time are white heads due to foot rots (see wheat disease update on 5-24-2019 available at http://entoplp.okstate.edu/pddl/advisory.htm), Fusarium head blight, and sooty mold. I’ve described and discussed Fusarium head blight in a previous update (5-16-2019 available at http://entoplp.okstate.edu/pddl/advisory.htm). Sooty mold on heads occurs when wheat has turned but cannot be harvested in a timely manner. Wet and humid conditions promote fungal growth on those heads (Figure 4). With time, these fungi can also partly start to grow on wheat seed still in the head, especially at the germ end of the seed. This can lead to a poorer quality of wheat and reduced seed germination

What is described above is confirmed for northwestern OK and the OK panhandle by Josh Bushong (NW OK Area Extn Agron Speclt) who reported seeing overall leaf health as deteriorating across NW OK as well as at field days this past week at Hooker, Balko and Goodwell (all in the OK panhandle). However, the wheat in these parts of Oklahoma should be sufficiently far along (mostly in dough stage) so that the impact on yield should be minimal. Be aware though that head diseases such as Fusarium head scab and sooty mold can affect grain quality and create major problems when the wheat is taken to the elevator.

--Bob Hunger, Extension Plant Pathologist, Oklahoma 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 WI, 05/31/19

The University of Wisconsin-Madison Field Crops Pathology crew has spent the last several days scouting winter wheat variety trials in south and south central Wisconsin. Wheat at all locations observed, had flag leaves fully emerged. Weather has been extremely wet and cool across the state. Despite the wet conditions, wheat was generally disease free. We are worried about the risk for Fusarium head blight (FHB) this year given the weather pattern we have been stuck in. Currently the Fusarium head blight Risk Model is showing mostly high levels of risk in the primary wheat growing region of the state. While no heads have emerged, heading will begin in the next 1-2 weeks. Pay close attention to the risk model and your local weather as we approach anthesis (flowering). I anticipate the risk to remain high as periods of rain and humidity persist. Fungicide products of choice to control FHB in Wisconsin include Caramba, Prosaro, and Miravis Ace. Multiple years worth of data in Wisconsin suggest that the best application window for any of these products begins at the start of anthesis until 5-7 days after the start of anthesis. Applying fungicide before anthesis or 7-10 days after anthesis will result in poor performance against vomitoxin accumulation, out of the product. For information pertaining to recent fungicide studies on winter wheat in Wisconsin, click this link and scroll to page 12 of the report: https://badgercropdoc.com/wp-content/uploads/sites/5/2018/12/2018-Fungic.... Other reports can be found at this link: https://badgercropdoc.com/research-summaries/.

--Damon Smith, Extension Plant Pathologist, University of Wisconsin-Madison

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 MD, 05/28/19

Flowering is all finished across all counties of Maryland now, except for a few late planted fields in the northern part of MD that may still be flowering. Currently the risk of FHB is low in these areas. For most parts, wheat is now in the grain filling stage. With the showers that we had at flowering, if you had a susceptible variety planted and missed application of fungicides at the correct time, there are high chances of substantial Fusarium Head Blight incidences. Consequently, tombstones (shriveled scabby kernels) and DON content may be a concern for the growers. To assess the incidence of FHB, you may randomly pick 20-25 heads of wheat per 1-2 acres and count the spikes having bleached spikelets. Fields with high incidence rates should be harvested separately from those with lower incidences. Harvesting from fields with high levels of FHB incidence should be done with higher fan speeds to remove lighter tombstone kernels. The farmers are advised to get the DON content analyzed in the grain before taking it to the market.

--Nidhi Rawat, Small grains Pathologist, University of Maryland

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