Fusarium Risk Assessment: 5/9/24

Nidhi Rawat, Small Grains Pathologist
University of Maryland, College Park

Wheat is mostly ending flowering across Maryland now, except for some late-planted fields. The FHB prediction map shows enhanced FHB risk. If your wheat flowered within the past 4-7 days, you are still in the window for FHB fungicide application. This season, we are also observing several foliar diseases such as stripe rust, powdery mildew, BYDV, and tan-spot in our variety trial plots. Some farmers are also reporting these issues from their fields. If you are considering the application of fungicides at this stage, use FHB fungicides: Miravis-Ace, Prosaro, Prosaro-Pro, or Sphaerex. These will control other fungal diseases, in addition to FHB, but not BYDV. For BYDV none of the fungicides can provide control, as it is a viral disease, and genetic resistance is the only real solution for it. Strobilurin-containing fungicides are not recommended for application at this stage.

Wheat Leaf Tip Necrosis Showing in Many Wheat Fields

Andrew Kness, Senior Agriculture Agent | akness@umd.edu and Nidhi Rawat, Small Grains Pathologist
University of Maryland

Over the past couple of weeks we have gotten several questions about yellowing flag leaves on wheat. Generally these symptoms are appearing widespread in fields. To the best of our knowledge we can attribute this to leaf burn or leaf tip necrosis (LTN) (Figure 1). This disorder is often a response to cold injury or wind, but can also manifest as a result of heat and drought stress. We have had widespread hot and dry conditions for several weeks across Maryland, which can trigger these symptoms, especially on lighter soils. These symptoms can also be intensified by specific leaf rust and stripe rust resistance genes and LTN severity can vary greatly between varieties. In any case, there is nothing you can do to remedy the situation.

Figure 1. Wheat leaves with symptoms of leaf tip necrosis. Note the dead tissue at the leaf tips.

Leaf tip necrosis may be confused with barley yellow dwarf virus (BYDV). BYDV is undoubtedly contributing to some of the symptoms in many of these fields, but it is probably not the sole factor causing these symptoms. LTN tends to cause death of the leaf tip resulting in necrotic brown tissue (Figure 1), whereas BYDV can cause a range of symptoms from yellowing of the leaf, which may or may not be accompanied with bronzing/purpling of the leaf tips (Figure 2). Notably with BYD, leaf tips do not die and become necrotic; whereas leaf tissue from LTN will become brown and dead starting at the leaf margins near the tip and work inward. Since BYDV is vectored by aphids, symptoms tend to be localized in hotspots in a field where aphids populations are high, whereas leaf burn and LTN more uniformly affect the entire field.

Figure 2. Symptoms of barley yellow dwarf virus. Leaf tips are yellow and purple/bronze but tissue is not dead.

Overview of Fungicides for Head Scab Control in Wheat

Andrew Kness, Senior Agriculture Agent | akness@umd.edu
University of Maryland Extension, Harford County

This article may come a little too late for some of you depending where you are in the state; but nevertheless, here is a review/reminder. As we get into May, wheat will begin flowering and we will have to consider fungicide applications to wheat to manage Fusarium head blight (FHB), also known as head scab. FHB is the most economically important disease of wheat, causing not only yield reductions, but more seriously, grain quality issues due to the production of the mycotoxin deoxynivalenol (DON), also called vomitoxin.

The pathogen that causes FHB, Fusarium graminearum, persists in wheat, small grain, and corn residue. It infects the wheat plant through the open flower, which is why flowering is such an important management timing for quality wheat production. Fusarium graminearum requires moist conditions and moderate temperatures (59-86 °F) to initiate infection. If these conditions are met during flowering, the pathogen will infect susceptible wheat varieties and cause disease.

Management of FHB requires a layered approach of IPM practices, with the major management practices being the selection of a good wheat variety and subsequent good planting and fertility practices, plus the use of a fungicide at flowering should the environmental conditions be conducive for FHB development. The wheatscab.psu.edu map can be helpful in predicting FHB risk to wheat around flowering.  Historically, this model has been over 70% effective at predicting FHB outbreaks and should be consulted when making fungicide decisions. If you decide to apply a fungicide to manage FHB, there are three important factors to consider: 1.) Timing, 2.) Application method, and 3.) Active ingredient.

As mentioned earlier, the pathogen can only infect wheat through the open flower, so you need to time your fungicide application as close to flowering, or Feekes Growth Stage 10.5.1, as possible (Figure 1). This growth stage is defined by the appearance of yellow anthers in the center of the wheat spike on at least 50% of the plants. Once this stage is reached, the application window is about 5-7 days. Some fungicide products are labelled for application as early as Feekes 10.3 (half head emergence); however, this timing is not as optimal as 10.5.1—so wait if you can.

wheat at start of anthesis
Figure 1. Wheat at Feekes 10.5.1, indicating proper fungicide timing for FHB management. Photo: A. Kness, Univ. of Maryland.

The second factor is application method. Most of our fungicides on wheat go on with a ground sprayer. For ground applications it is important to achieve good coverage of the wheat heads, not the foliage. To do this, spray volumes should be at least 15-20 gallons/acre and you should use bi-directional spray nozzles angled forward and backwards. This combination of spray volume and angled nozzles results in thorough coverage of the wheat heads. Aerial applications should be done at 5 gallons/acre for maximum coverage.

The final consideration is fungicide active ingredient. Triazole and HDMI fungicides work best on FHB. Products include: Prosaro Pro, Prosaro, Miravis Ace, Saphaerex, Proline, and Caramba; Folicur has less efficacy than the others and Tilt is no longer effective on FHB. An added benefit is that these products will also do a good job of keeping other fungal diseases at bay during grain fill. Do not apply any group 11 (Qoi/strobilurin) fungicides such as Aproach, Headline, or Quadris after heading as these products can actually increase DON levels in the grain.

Fusarium Risk Assessment 4/30/24

Nidhi Rawat, Small Grains Pathologist
University of Maryland, College Park

Wheat is currently flowering or will soon flower across the state of Maryland. Flowering is when yellow anthers emerge out of the wheat spikes. This is again that year, in which if you planted a resistant variety, you would be okay without spraying fungicides for controlling Fusarium head Blight (FHB risk map: top picture). However, if your planted variety is not FHB resistant, you should consider application of FHB fungicides (FHB risk map: lower picture). If you are planning to apply fungicides for FHB, remember that triazole-containing fungicides (Miravis-Ace, Prosaro, Prosaro-Pro, and Sphaerex) should be used for controlling FHB. They can control other fungal pathogens like powdery mildew, rusts, in addition to scab. Strobilurin-containing fungicides should not be used at this stage. These fungicides do not need to be tank mixed with another product for spraying. The fungicide products should be applied at the full rate recommended by the manufacturers. Aerial application at a rate of 5 gallons per acre or ground application at 15 gallons per acre with 300-350 um droplet size is recommended. Spray nozzles should be angled at 30°-45° down from horizontal, toward the grain heads, using forward- and backward-mounted nozzles or nozzles with a two directional spray, such as Twinjet nozzles.

Fusarium Risk Assessment 4/24/2024

Nidhi Rawat, Small Grains Pathologist
University of Maryland, College Park

Wheat on the Eastern shore of Maryland is heading and should start flowering within a week or so. Wheat in the north-western part (Frederick, Carroll, Hartford counties) is also close to heading or has started heading. The FHB fungal pathogen infects the wheat plants at the flowering stage (when the yellow anthers emerge from the heads), which is the stage at which the application of fungicides is conducted in wheat. The FHB map currently does not show high risk, especially for a genetically resistant variety. However, keeping an eye on the forecasts and weather patterns over the next few days as your wheat flowers is recommended. If you are planning to apply fungicides for FHB, remember that triazole-containing fungicides (Miravis-Ace, Prosaro, Prosaro-Pro, and Sphaerex) should be used for controlling FHB. They can control other fungal pathogens like powdery mildew as well, in addition to scab. Strobilurin-containing fungicides should not be used at this stage.

Fusarium Head Blight Risk 4/24/2024.

FHB RISK ASSESSMENT MARYLAND Date 4/11/2024

Nidhi Rawat, Small Grains Pathologist
University of Maryland

Welcome to the wheat and barley heading and flowering season, Maryland! This is the first FHB risk forecast for this season from me, and I will continue to provide you with regular commentaries over the next 6-7 weeks. Wheat is some weeks away from flowering, but barley is starting/ will soon start to head, especially in the Eastern shore of the state. Unfortunately, for barley, there are no FHB-resistant varieties available so far. So, if you have planted barley, keep monitoring closely for the FHB risk over the next couple of weeks. With the rainy spell of the last week, and some more rain forecasted this week, currently, the Epidemiological models are showing elevated FHB risk over the next 6 days. So, if your barley is starting heading you might consider applying fungicides on it. If you are still some weeks away from your barley heading, keep monitoring for the risk. Remember, the best stage for applying FHB fungicides on barley is when the heads are completely out of the boots. The FHB fungicides are triazole-containing products (Miravis-Ace, Prosaro, Prosaro-Pro, Sphaerex). Do not apply strobilurin-containing fungicides after heading. Wheat is not at a stage susceptible to FHB right now.

Some barley growers from across the state reported stunting, yellowing, and death of barley plants in their fields. The most probable cause of this issue in my opinion is freeze injury. Sudden dips in temperature after the plants caught up after winter may have led to the issue. I have discussed this issue with the other regional pathologists from the US, and they also report similar issues in North Carolina, Pennsylvania, and New York. They also think it to be a result of cold injury.

UMD Grain Marketing Site Updated for 2024: Field Crop Budgets

Shannon Dill, Principal Agriculture Agent | sdill@umd.edu
University of Maryland Extension, Talbot County

The University of Maryland Extension has updated www.go.umd.edu/grainmarketing site with new input data and spray programs for the 2024 field crop budgets.

Crop Budgets

Cost of production is very important when making decisions related to your farm enterprise and grain marketing. Preliminary surveys from 2024 UME Winter Crop Production meetings report 66% of farmers believe input costs are the greatest challenges facing their farm operation. Enterprise budgets provide valuable information regarding individual enterprises on the farm. This tool enables farm managers to make decisions regarding enterprises and plan for the coming production year. An enterprise budget uses farm revenue, variable cost, fixed cost, and net income to provide a clear picture of the financial health of each farm enterprise.

The 2024 Maryland enterprise budgets were developed using average yields and estimated input costs based on producer and farm supplier data. Fertilizer prices, pesticide availability, and fuel expenses have fluctuated greatly. The figures presented are averages and vary greatly from one farm and region to the other. It is, therefore, crucial to input actual farm data when completing enterprise budgets for your farm.

Cost Per Acre, 2024
Year Corn

No Till

Corn

Conventional

Soybeans Wheat Wheat/Beans
2021 $540 $592 $346 $401 $608
2023 $736 $800 $423 $538 $800
2024 $690 $749 $410 $514 $752
Difference 23-24 -$46 -$51 -$13 -$24 -$48
Percent Change -6% -6% -3% -4% -6%

How to Use University Enterprise Budgets

The enterprise budgets can be used as a baseline for your operation, and you can change these budgets to include your production techniques, inputs, and overall management. The budgets are available electronically in PDF or Excel. Use this document as a start or reference to create your crop budgets. Contact information is on the website if you have problems downloading any information.

2024 Crop Summary

Cost per acre expenses for 2024 have decreased a small amount from 2023 record highs. Based on estimates received cost of production includes: corn no-till costs $690 per acre, corn conventional $749 per acre, soybeans $410 per acre and wheat $514 per acre. While these are slightly (3-6%) lower than 2023 they are still 16%-22% higher than prices just 3 years ago (2021).

Farmers May Fertilize Small Grains With Commercial Fertilizer Beginning February 15

Reposted from the Maryland Department of Agriculture

The Maryland Department of Agriculture today announced that farmers who planted small grains for harvest last fall may “top dress” these crops with commercial fertilizer in accordance with their nutrient management plans, beginning February 15, provided that crop and field conditions remain favorable.

University of Maryland researchers have determined that crop growth stages vary across the state. The Lower Eastern Shore of Maryland and Southern Maryland appear to have met the appropriate time to top-dress. However, the Maryland Department of Agriculture has given approval to all Maryland farmers to begin applying fertilizer to small grains, as long as crops have reached the “green-up” stage before applying fertilizer. The University recommends split applications of spring nitrogen with the first application occurring at “green-up” and the second application when the crops begin to joint. Check individual field conditions and avoid running heavy equipment across saturated soils.

The determination follows Maryland’s nutrient management regulations. As a reminder, manure may not be applied to fields until March 1.

For additional information on Maryland’s nutrient application requirements, contact the MDA’s Nutrient Management Program at 410-841-5959.

For a directory of University of Maryland Nutrient Management Planners, visit: https://extension.umd.edu/resource/ume-nutrient-management-advisors/.

October 2023 Grain Market Update

Information from USDA WASDE report

Attached is the summary for the October 2023 WASDE.

Corn

This month’s 2023/24 U.S. corn outlook is for reduced supplies, lower feed and residual use and exports, and smaller ending stocks. Corn production is forecast at 15.064 billion bushels, down 70 million on a cut in yield to 173.0 bushels per acre. Corn supplies are forecast at 16.451 billion bushels, a decline of 160 million bushels from last month, with lower production and beginning stocks. Exports are reduced by 25 million bushels reflecting smaller supplies and slow early-season demand. Feed and residual use is down 25 million bushels based on lower supply. With supply falling more than use, corn ending stocks for 2023/24 are lowered 110 million bushels. The season-average corn price received by producers is raised 5 cents to $4.95 per bushel.

Soybean

Soybean production is forecast at 4.1 billion bushels, down 42 million on lower yields. Harvested area is unchanged at 82.8 million acres. The soybean yield is projected at 49.6 bushels per acre, down 0.5 bushels from the September forecast. The largest production changes are for Kansas, Michigan, and Nebraska. With lower production partly offset by higher beginning stocks, supplies are reduced 24 million bushels. Soybean exports are reduced 35 million bushels to 1.76 billion with increased competition from South America. Soybean crush is projected at 2.3 billion bushels, up 10 million, driven by higher soybean meal exports and soybean oil domestic demand. Soybean oil domestic use is raised in line with an increase for 2022/23. With lower exports partly offset by increased crush, ending stocks are unchanged from last month at 220 million bushels. 

Wheat

The outlook for 2023/24 U.S. wheat this month is for higher supplies, increased domestic use, unchanged exports, and higher ending stocks. Supplies are raised 85 million bushels, primarily on higher production as reported in the NASS Small Grains Annual Summary, released September 29. Domestic use is raised 30 million bushels, all on higher feed and residual use. The NASS Grain Stocks report released September 29 indicated a higher year-to-year increase for first quarter (June-August) domestic disappearance than previously expected. Exports remain at 700 million bushels with several offsetting by-class changes. Projected ending stocks are raised by 55 million bushels to 670 million, up 15 percent from last year. The season average farm price is reduced $0.20 per bushel to $7.30 on higher projected stocks and expectations for futures and cash prices for the remainder of the marketing year.

Scout for Aphids in Small Grains

Kelly Hamby, Associate Professor and Extension Specialist, University of Maryland and
David Owens, Extension Entomologist, University of Delaware

Figure 1. Barley Yellow Dwarf patch in a field of malting barley, March 2023. Photo: David Owens, Univ. of Delaware.

Last season, aphids transmitted an unusual amount of barley yellow dwarf virus (BYDV) to wheat and barley across the Delmarva Peninsula. BYDV is particularly important when it infects plants in the fall. Fall BYDV infections can stunt plants (noticed as early as green-up, Figure 1) and cause more serious yield loss than spring infections. Our most common small grain aphid species are bird cherry oat aphid (Figure 2) and English grain aphid, although bird cherry oat aphid are associated with greater and more severe incidence of BYDV.

Figure 2. Bird cherry-oat aphids.

Historically, planting after the Hessian fly-free date (Table 1) reduced the likelihood of fall BYDV infection. However, fly-free dates were calculated more than 100 years ago, and it is now not uncommon for our first killing frosts to occur in late October or even November. Long falls with milder weather allow more time for aphids to colonize fields and potentially transmit the virus. Small grains varieties vary in their susceptibility to BYDV, and planting varieties with at least some tolerance can help. Unfortunately, resistant varieties are not available in barley. Finally, monitoring and managing the aphid vectors may be necessary.

Identifying bird cherry-oat aphid: A magnifying hand lens is required to identify aphids. Bird cherry-oat aphid ranges from orange green to olive green to greenish black. Wingless individuals typically have a reddish orange patch around the base of the cornicles (tail pipes). Winged individuals tend to be very dark. Their legs, cornicles, and antennae are similar in color to their bodies and medium in size.

Monitoring and thresholds: Typically, monitoring aphids in the fall and at green-up provides the best chance of identifying and mitigating BYDV risk. Scout ten locations per field avoiding field margins and look at 1 ft of row in each, making sure to look at the crown (at or below ground level), at the stem, and on the undersides of leaves. English grain aphids tend to feed on the uppermost portions of the plants while bird cherry oat aphids tend to cluster on the lower portions, especially in barley.

University extension threshold recommendations vary by region. In southern states, 6 aphids/row-ft is considered justification for a treatment in the fall. North Carolina uses a threshold of 20 aphids/row-ft where BYDV has been a problem and cold weather is not in the 7 day forecast. For other small grains, consider increasing the threshold to 25-50 aphids per foot of row.

In 2022, one of the malting barley fields sampled averaged 17 aphids per row-ft in early November. Because of unusually warm winter weather in which average temperatures were greater than 38 degrees, aphid populations peaked in one field at 235 aphids per row-ft that had averaged 1.8 per row-ft in November. This highlights the need to regularly monitor aphid populations during periods of mild weather.

Natural enemies: A number of natural enemies feed upon or parasitize aphids and they often do a good job keeping aphid populations down. One natural enemy per 50-100 aphids should be sufficient to control aphid populations. In addition, they are good at finding aphids even when their populations are low. Small wasps that develop within aphids leaving behind “mummy” aphids (Figure 3A), lady beetles, lacewing larvae (Figure 3B), and flower fly larvae (Figure 3C) are especially common aphid natural enemies. Insecticides will also kill these natural enemies.

Figure 3. Aphid natural enemies A) parasitoid wasp and golden or tan colored “mummy” aphids, B) lacewing larva eating aphids, C) flower fly larva eating aphids. Images: David Cappaert, Bugwood.org.

Insecticides: Seed treatments (e.g., Cruiser, Gaucho) provide some protection from fall aphids, but do not continue to provide protection into the spring and are not economic in years where aphids do not occur. Due to the differences in economics and BYDV susceptibility of malting barley varieties, seed treatments may be more useful than in feed barley or wheat. We generally recommend a foliar insecticide when aphid populations reach threshold. Small grain aphids are generally quite susceptible to insecticides. Pyrethroid products (e.g., Warrior) or a pyrethroid-neonicotinoid mix (e.g., Endigo, labeled for barley only) work well for aphid control.

 

Table 1. Hessian fly-free dates for Maryland and Delaware counties

State County Date
Maryland Allegany Sept. 27
Anne Arundel Oct. 7
Baltimore Oct. 2
Calvert Oct. 8
Caroline Oct. 7
Carroll Sept. 28
Cecil Oct. 3
Charles Oct. 8
Dorchester Oct. 9
Frederick Oct. 2
Garrett Sept. 20
Harford Oct. 1
Howard Oct. 2
Kent Oct. 6
Montgomery Oct. 4
Prince George’s Oct. 7
Queen Anne’s Oct. 7
Somerset Oct. 10
St. Mary’s Oct. 9
Talbot Oct. 8
Washington Oct. 1
Wicomico Oct. 10
Worcester Oct. 11
Delaware Kent Oct. 8
New Castle Oct. 3
Sussex Oct. 10

More information:

Kleczewski, N., Cissel, B., Whalen, J. 2016. Barley Yellow Dwarf Management in Small Grains. http://cdn.extension.udel.edu/wp-content/uploads/2015/10/14051904/BYDV-Final-Draft-9-12-16.pdf.

Flanders, K., Herbert, A., Buntin, D., Johnson, D., Bowen, K., Murphy, J. F., Chapin, J., Hagan, A. 2006. Barley Yellow Dwarf in Small Grains in the Southeast. https://entomology.ca.uky.edu/files/efpdf1/ef150.pdf.

Owens, D. and B. Cissel. Insect Control in Small Grains (for Grain only) – 2020. https://www.udel.edu/content/dam/udelImages/canr/pdfs/extension/sustainable-agriculture/pest-management/Insect_Control_in_Small_Grains_2020.pdf.