2022 Wisconsin Fungicide Test and Disease Management Summary Now Available!

/in , , , , , /by

Brian Mueller, Researcher II, UW-Madison, Plant Pathology

Damon Smith, Associate Professor and Extension Specialist, UW-Madison, Plant Pathology

Each year the Wisconsin Field Crops Pathology Program conducts a wide array of fungicide and disease management tests on alfalfa, corn, soybeans, and wheat. These tests help inform researchers, practitioners, and farmers about the efficacy of certain fungicide products on specific diseases and how to pair them with other disease management strategies. We hope you find this report useful in making decisions for the 2023 field season.

The 2022 Wisconsin Field Crops Fungicide Test and Disease Management Summary is available by clicking here. These tests are by no means an exhaustive evaluation of all products available, but can be used to understand the general performance of a particular fungicide in a particular environment. Keep in mind that the best data to make an informed decision, come from multiple years and environments. To find fungicide performance data from Wisconsin in other years, visit the Wisconsin Fungicide Test Summaries page. You can also consult publication A3646 – Pest Management in Wisconsin Field Crops to find information on products labeled for specific crops and efficacy ratings for particular products. Additional efficacy ratings for some fungicide products for corn foliar fungicides, soybean foliar and seed-applied fungicides, and wheat foliar fungicides can be found on the Crop Protection Network website.

Mention of specific products in these publications are for your convenience and do not represent an endorsement or criticism. Remember that this is by no means a complete test of all products available.  You are responsible for using pesticides according to the manufacturers current label. Some products listed in the reports referenced above may not actually have an approved Wisconsin pesticide label. Be sure to check with your local extension office or agricultural chemical supplier to be sure the product you would like to use has an approved label.  Follow all label instructions when using any pesticide. Remember the label is the law!

Are My Fungicides Messing with the Good (Microbes) Guys?

/in , , , /by

The following blog post was written as a part of a graduate level class assignment at the University of Wisconsin-Madison. Of course much more work needs to be done in this area, but there is some interesting “food for thought” and should be considered the next time you might want to spray a fungicide.    ~Damon Smith, Professor and Extension Specialist

 

Kelly Debbink, master’s student, Department of Plant Pathology, University of Wisconsin-Madison

Have you ever wondered if fungicides can negatively impact soil microbes? Since their job is to kill fungi, it seems logical that they may have this effect on the fungi in the soil, right? This thought process is exactly what led me into reading a few too many published studies related to the topic.

Background

Let me start with a bit of what we know about soil microbes (mainly fungi and bacteria). Some microbes form symbiotic relationships with plants, through which they can colonize the root system (rhizosphere), the above ground plant surfaces (phyllosphere), and even internal tissues (endosphere). These microbes can help plants access nutrients and water, fight off diseases caused by other pathogenic microbes, and deal with stressful environments. Many other types of microbes may not form direct relationships with plants, but still live in the soil and provide services, like breaking down nutrients.

To carry out many of these useful activities, microorganisms produce diverse groups of enzymes. They are proteins that work to facilitate different processes and are necessary in many services related to soil health, including decomposing organic matter, nutrient cycling, and degrading hazardous compounds. Enzyme amounts are sensitive to environmental factors like pH and soil organic matter as well as management practices like crop type, chemical use, and fertilizer use. Any alteration of the soil microbial community will lead to changes in enzyme production, so they are commonly used as a soil health indicator. Lower enzyme levels are generally tied to less fertile soil and less productive crops.

So, if microbes are responsible for all these services, could we be causing them harm and hindering some of these services when we apply fungicides?

In my search I was specifically hoping to find field research instead of lab research, so I could find information that was a closer proximation to real life conditions. I will admit that most studies I found on this topic were performed in the lab by removing soil from an agricultural region, dosing it with fungicides, and running soil health tests on it. I did find a few field studies in which treated and non-treated plots were compared in normal cropping systems. These studies were all a bit different in their approaches to measuring changes, and they tested many different fungicides with different modes of action, so I would not compare these studies side-by-side to each other, but I will share some general trends that appeared in their results.

Soil Microbes

To start, there do appear to be shifts in some of the fungal and bacterial communities related to fungicide treatments. In a study that looked at seed coatings (fungicides & insecticides), these did not appear to decrease the richness (total # of microbe species) but did shift the abundance of different groups of microbes. In another study, the number of culturable bacteria and fungi were decreased, which at least suggested a decrease in richness of the subset of microbes that are culturable on lab media. Other lab experiments showed declines or shifts in the fungal community, but differing results on the bacterial community (they may decline as well or may increase). In some conditions, bacteria may be able to thrive once they have decreased competition from fungi. In one field trial, the label application rate and 2x the label rate led to short-term declines in measures of viable microbes. These declines all recovered by harvest. Additionally, this study tested 10x the label rate, but in this treatment, microbes remained low through harvest.

Soil Enzymes

Shifts in soil enzymes related to microbial activity and nutrient cycling were observed in multiple field trials. The general trend appears to be that at lower fungicide application levels, like label rate and twice the label rate, these enzymes may shift up and down, but often return near normal levels by harvest time. In contrast, the study that applied 10x the label rate observed declines in most enzymes that did not recover by harvest. This suggests that improper overuse or accumulation of fungicides may be detrimental to soil functions like nutrient cycling.

Conclusion

Overall, there are many environmental conditions that play a role in soil fungal and bacterial populations and enzyme activity. Many management decisions can have an impact on these, like crop rotation, tillage, and fertilizer use. Chemical use, like fungicides and other types of pesticides, likely also play a role in at least short-term shifts in soil microbes and enzyme activity. Obviously, the main goal of these fungicides is to control disease, and they are certainly a useful and necessary tool to protect crop yields and minimize disease. However, these studies do help remind us that there can be negative soil health effects to their overuse, in addition to the increased risk of pesticide resistance. It’s a good reminder that fungicides are only one tool in the toolbox, and other management decisions like choosing resistant varieties can help us control disease with fewer necessary fungicide applications.

 

References:

Background

Turner TR, James EK, Poole PS. The plant microbiome. Genome Biol. 2013 Jun 25;14(6):209. doi: 10.1186/gb-2013-14-6-209. PMID: 23805896; PMCID: PMC3706808.

Chettri, D., Sharma, B., Verma, A. K., & Verma, A. K. (2021). Significance of Microbial Enzyme Activities in Agriculture. Microbiological Activity for Soil and Plant Health Management, 351–373. https://doi.org/10.1007/978-981-16-2922-8_15

Field Trials

Hou, K., Lu, C., Shi, B., Xiao, Z., Wang, X., Zhang, J., Cheng, C., Ma, J., Du, Z., Li, B., & Zhu, L. (2022). Evaluation of agricultural soil health after applying pyraclostrobin in wheat/maize rotation field based on the response of soil microbes. Agriculture, Ecosystems & Environment, 340, 108186. https://doi.org/10.1016/j.agee.2022.108186

Saha, A., Pipariya, A., & Bhaduri, D. (2016). Enzymatic activities and microbial biomass in peanut field soil as affected by the foliar application of tebuconazole. Environmental Earth Sciences, 75(7). https://doi.org/10.1007/s12665-015-5116-x

‌ Nettles, R., Watkins, J., Ricks, K., Boyer, M., Licht, M., Atwood, L. W., Peoples, M., Smith, R. G., Mortensen, D. A., & Koide, R. T. (2016). Influence of pesticide seed treatments on rhizosphere fungal and bacterial communities and leaf fungal endophyte communities in maize and soybean. Applied Soil Ecology, 102, 61–69. https://doi.org/10.1016/j.apsoil.2016.02.008

‌Lab Experiments

Han, L., Xu, M., Kong, X., Liu, X., Wang, Q., Chen, G., Xu, K., & Nie, J. (2022). Deciphering the diversity, composition, function, and network complexity of the soil microbial community after repeated exposure to a fungicide boscalid. Environmental Pollution, 312, 120060. https://doi.org/10.1016/j.envpol.2022.120060

‌ Cycoń, M., Piotrowska-Seget, Z., & Kozdrój, J. (2010). Responses of indigenous microorganisms to a fungicidal mixture of mancozeb and dimethomorph added to sandy soils. International Biodeterioration & Biodegradation, 64(4), 316–323. https://doi.org/10.1016/j.ibiod.2010.03.006

 

2022 Badger Crops and Soils Update Meetings

/in , , , , , /by

The annual UW Agronomy, Pest Management and Soil, Water, and Nutrient Management meetings are moving to a new format this year and will be offered as a single day-long program. Two in-person sessions as well as a virtual option will be offered. In-person sessions in Green Bay and La Crosse will follow the same agenda. The virtual option will follow a similar but abbreviated agenda.

This year’s program will be focused on the theme of “Achieving a Positive Return on Investment in an Era of High Input Costs (a.k.a Small steps, Big change).” The meetings will present the latest information on agronomic, pest, and nutrient management research coming out of UW with a lens to on-farm application.

For details and to register for the event, please CLICK HERE or scan the QR code in the attached flyer. We are looking forward to seeing you and kicking off a busy winter meeting season!

Wisconsin Winter Wheat Disease Update – June 1, 2022

/in , , /by

Damon L. Smith, Extension Field Crops Pathologist, Department of Plant Pathology, University of Wisconsin-Madison

In Wisconsin, wheat diseases have been nearly non-existent up to this point. Cool weather has generally kept wheat disease at low levels. However, increase frequency of rain events and moderate temperatures over the next 7-10 days will likely increase disease risk, especially Fusarium head blight (FHB or Scab). 

Fusarium head blight risk for susceptible winter wheat varieties for June 1, 2022.

We are entering the window for fungicide applications for FHB here in Wisconsin. Currently the Fusarium Head Blight Risk tool is predicting more areas of moderate to high risk in Wisconsin for FHB than it did a week ago (Fig. 1). If highly susceptible wheat varieties were planted in Wisconsin, the current risk is high across most of the state. Rainy conditions in the next seven days will likely push this risk higher. Now is the time to consider a fungicide application to manage FHB in Winter wheat in the state.

In winter wheat in Wisconsin, research has demonstrated that the best time to apply fungicides is between the start of anthesis (first anthers out) to 7 days after the start of anthesis. This same research has demonstrated that waiting to apply fungicides 5 days after the start of anthesis, optimizes deoxynivalenol (DON or vomitoxin) reductions in finished wheat. This is due to the fact that head emergence in Wisconsin can be very uneven. Waiting 5 days after the start of anthesis may help with optimizing application timing to maximize heads flowering and receiving fungicide protection. Fungicide choice is also critical, with Prosaro, Caramba, and Miravis Ace providing the most consistent control of Fusarium head blight and reduction of DON in trials in Wisconsin. Fungicides containing strobilurin fungicides should be avoided after the boot stage of wheat as these products can increase DON levels in finished grain. Fungicide efficacy information from Wisconsin can be found at https://badgercropdoc.com/research-summaries/. National ratings for fungicide efficacy of small grains can be found HERE. Additional thoughts on using fungicide on wheat can be found in this Bumper Crops Video.

We also know that in Wisconsin, that a fungicide application targeted to manage FHB will pay for itself almost every time. You can find published research information on the probability of a return on fungicide investment by clicking HERE. Be sure to focus on comparing the “current” level of treatment to the “mid-level” of treatment in the publication. The only difference between these two treatment plans was the application of fungicide at Feekes 10.5.1 to manage FHB. The “mid-level” plan returned on average more than $120 per acre above the “current” management plan in our trials.

Keep scouting!

 

Wisconsin Winter Wheat Disease Update – May 24, 2022

/in , , /by

Damon L. Smith, Extension Field Crops Pathologist, Department of Plant Pathology, University of Wisconsin-Madison

Figure 1. Fusarium Head Blight Risk Map – May 24, 2022.

Winter Wheat is Wisconsin is in the “boot “or heading in the southern part of the state. Currently the Fusarium Risk Assessment Map is showing low risk for Fusarium head blight development (Fig 1). Rain is forecast for the next several days, thus, the risk is likely to climb as we approach wheat heading and flowering. Wheat farmers and consultants should pay attention to weather closely over the next several weeks as the decision to apply fungicide will need to be made during this time.

In winter wheat in Wisconsin, research has demonstrated that the best time to apply fungicides is between the start of anthesis (first anthers out) to 7 days after the start of anthesis. This same research has demonstrated that waiting to apply fungicides 5 days after the start of anthesis, optimizes deoxynivalenol (DON or vomitoxin) reductions in finished wheat. This is likely since head emergence in Wisconsin can be very uneven. Waiting 5 days after the start of anthesis may help with optimizing application timing to maximize heads flowering and receiving fungicide protection. Fungicide choice is also critical, with Prosaro, Caramba, and Miravis Ace providing the most consistent control of Fusarium head blight and reduction of DON in trials in Wisconsin. Fungicides containing strobilurin fungicides should be avoided after the boot stage of wheat as these products can increase DON levels in finished grain. Fungicide efficacy information from Wisconsin can be found at https://badgercropdoc.com/research-summaries/. National ratings for fungicide efficacy of small grains can be found HERE. Additional thoughts on using fungicide on wheat can be found in this Bumper Crops Video.

2021 Wisconsin Fungicide Test and Disease Management Summary Now Available

/in , , , , /by

Brian Mueller, Researcher II, UW-Madison, Plant Pathology

Damon Smith, Associate Professor and Extension Specialist, UW-Madison, Plant Pathology

Mimi Broeske, Distinguished Editor, UW-Madison, Nutrient and Pest Management Program

Each year the Wisconsin Field Crops Pathology Program conducts a wide array of fungicide and disease management tests on alfalfa, corn, soybeans, and wheat. These tests help inform researchers, practitioners, and farmers about the efficacy of certain fungicide products on specific diseases and how to pair them with other disease management strategies. We hope you find this report useful in making decisions for the 2022 field season.

The 2021 Wisconsin Field Crops Fungicide Test and Disease Management Summary is available by clicking here. These tests are by no means an exhaustive evaluation of all products available, but can be used to understand the general performance of a particular fungicide in a particular environment. Keep in mind that the best data to make an informed decision, come from multiple years and environments. To find fungicide performance data from Wisconsin in other years, visit the Wisconsin Fungicide Test Summaries page. You can also consult publication A3646 – Pest Management in Wisconsin Field Crops to find information on products labeled for specific crops and efficacy ratings for particular products. Additional efficacy ratings for some fungicide products for corn foliar fungicides, soybean foliar and seed-applied fungicides, and wheat foliar fungicides can be found on the Crop Protection Network website.

Mention of specific products in these publications are for your convenience and do not represent an endorsement or criticism. Remember that this is by no means a complete test of all products available.  You are responsible for using pesticides according to the manufacturers current label. Some products listed in the reports referenced above may not actually have an approved Wisconsin pesticide label. Be sure to check with your local extension office or agricultural chemical supplier to be sure the product you would like to use has an approved label.  Follow all label instructions when using any pesticide. Remember the label is the law!

2021 Wisconsin Pest Management Update Meetings (In-Person Events Cancelled; Virtual Offering Only)

/in , , , , , /by

After much deliberation, we made the difficult decision to pivot the 2021 Wisconsin Pest Management Update Meetings from a hybrid model to all virtual because of continued COVID-19 concerns and low registration numbers. Thus, the in-person events at Darlington (November 16, 2021), Chippewa Falls (November 17, 2021) and Kimberly (November 18, 2021) are now cancelled.

We will maintain the virtual offering on Friday November 19th(9:00 AM to Noon) and are adding a second virtual offering of the same program on Tuesday November 16th (1:00 PM to 4:00 PM) so participants can pick the option that best fits their schedule.

To register for one of the virtual events, please go to the following link: https://go.wisc.edu/8tufvc

This year’s speakers will include:

  • Mark Renz, Perennial Cropping Systems Extension Weed Specialist
  • Rodrigo Werle, Annual Cropping Systems Extension Weed Specialist
  • Nick Arneson, Extension Outreach Specialist, weeds
  • PJ Leisch Extension Entomology Diagnostician
  • Damon Smith, Extension Field Crops Pathologist

Topics will include updates in the area of weed, pest, and disease management along with a panel discussion and Q&A regarding the pest management challenges related to planting soybeans early.

Three (3) Pest Management CCA CEUs have been requested for this event.

Registration includes PDF of A3646 Pest Management In Wisconsin Fields.

We apologize for any inconvenience this decision may cause.

Pest Management Update Team

Save the Dates and Attend the 2021 Pest Management Update Meetings

/in , , , , /by

For 2021, the UW-Madison, Division of Extension and UW-Madison, Nutrient and Pest Management Program (NPM) will host the Pest Management Update Meetings as a hybrid event with (3) in-person meetings and (1) virtual option. All in-person meetings will be held from 1- 4pm local time at the venue listed for each location below. Check in will begin at 12:30pm with light refreshments available during the event. 

This year’s speakers include: Mark Renz, Perennial Cropping Systems Extension Weed Specialist; Rodrigo Werle, Annual Cropping Systems Extension Weed Specialist; Nick Arneson, Weed Science Outreach Specialist; PJ Liesch Extension Entomology Diagnostician; and Damon Smith, Extension Field Crops Pathologist. Topics will include updates in the area of weed, insect and disease management. A panel discussion and Q&A regarding the pest management challenges related to planting soybeans early will follow. 

The cost for the in-person events will be $50 per person and include a packet with materials including a hardcopy of A3646 Pest Management in Wisconsin Field Crops. This year ONLY, all in-person attendants will also receive a free copy of A Farmer’s Guide to Wheat Diseases, which is a $30 value. UW COVID safety protocols will be followed during the event. 

The cost for the virtual event will be $20 per person with pre-registration required. The virtual registration will include links to PDFs of materials and a PDF version of the A3646 publication. 

Below and in the attached flier are the dates, locations, and times for each event. Be sure to contact and register ONLY at the location you plan to attend. For the virtual option, links will be sent closer to the event.

 SOUTHERN WI 

Tuesday November 16 

1pm-4pm 

 Ames Road Multi-Purpose Building 11974 Ames Rd, Darlington, WI 53530 

Josh Kamps, UW-Madison, Division of Extension 

Dan Smith, UW-Madison NPM Program 

Register with Sara Schilling 

608-776-4820 or 

sara.schilling@wisc.edu 
NORTHWEST WI 

Wednesday November 17

1pm-4pm 

 Avalon Hotel and Conference Center 

1009 W Park Ave. 

Chippewa Falls, WI 54729 

Jerry Clark, UW-Madison, Division of Extension Kolby Grint, UW-Madison NPM Program 

Register with Jerry Clark 

715-726-7955 or 

jerome.clark@wisc.edu 
NORTHEAST WI 

Thursday November 18 

1pm-4pm 

 Liberty Hall Banquet/ Conference Center 

800 Eisenhower Dr, Kimberly, WI 54136 

Kevin Jarek, UW-Madison, Division of Extension Jamie Patton, UW-Madison NPM Program 

Register with Kevin Jarek 

kevin.jarek@wisc.edu or ina.montgomery@outagamie.org 

(920)-832-4763 
VIRTUAL 

Friday November 19

9am-noon 

 Kimberly Schmidt, UW-Madison, Division of Extension Dan Marzu, UW-Madison NPM Program 

Register at https://patstore.wisc.edu/secure/browse_ cat.asp?category_id=39 

Wisconsin Winter Wheat Disease Update – May 28, 2021

/in , , , /by

Damon L. Smith, Extension Field Crops Pathologist, Department of Plant Pathology, University of Wisconsin-Madison

Figure 1. Fusarium head blight risk for susceptible winter wheat varieties for Wisconsin as of May 28, 2021.

Winter wheat in Southern and South-central Wisconsin is quickly approaching anthesis. By early next week the window of opportunity to apply fungicide for Fusarium head blight (FHB; scab) will be here. Currently the risk for FHB is variable and ranges from low to high depending on where you are in the state (Figure 1). Given the recent rain events and rising temperatures, I think the risk is there for FHB next week. This situation should be monitored closely and a timely fungicide application decision should be made. In my previous post, I talk about how to manage FHB.  There are essentially three options for products in Wisconsin for control of FHB. These include Prosaro, Caramba, and Miravis Ace. All also have efficacy against other foliar diseases too. Remember, your window of opportunity to spray for FHB ranges from the start of anthesis (flowering) to about 7 days after the start of anthesis.

Stripe rust still remains unidentified in the state. Confirmed reports of stripe rust are only as close as central Illinois (Figure 2). Continue to remain diligent in scouting for this disease. Remember that fungicides for control of FHB will also be efficacious for stripe rust. Thus, we should be able to “kill two birds with one stone” when spraying for FHB.

Figure 2. Confirmed stripe rust reports for the U.S. as of May 28, 2021.

Reports of powdery mildew continue to come in.  Remember that the FHB fungicide treatments will control this disease. So at this point, two applications of fungicide are not needed. A well-timed FHB-focused fungicide app should help slow powdery mildew.

Get out there and scout, scout, scout!

2020 Wisconsin Field Crops Pathology Fungicide Tests Summary Now Available

/in , , , , /by

Damon Smith, Extension Field Crops Pathologist, Department of Plant Pathology, University of Wisconsin-Madison

Brian Mueller, Assistant Field Researcher, Department of Plant Pathology, University of Wisconsin-Madison

Each year the Wisconsin Field Crops Pathology Program conducts a wide array of fungicide tests on alfalfa, corn, soybeans, and wheat. These tests help inform researchers, practitioners, and farmers about the efficacy of certain fungicide products on specific diseases. This year we were a bit delayed in publishing the report, due to the challenges of COVID-19. However, we do appreciate your patience and hope you find the report useful in making decisions for the 2021 field season.

The 2020 Wisconsin Field Crops Fungicide Test Summary is available by clicking here. These tests are by no means an exhaustive evaluation of all products available, but can be used to understand the general performance of a particular fungicide in a particular environment. Keep in mind that the best data to make an informed decision, come from multiple years and environments. To find fungicide performance data from Wisconsin in other years, visit the Wisconsin Fungicide Test Summaries page. You can also consult publication A3646 – Pest Management in Wisconsin Field Crops to find information on products labeled for specific crops and efficacy ratings for particular products. Additional efficacy ratings for some fungicide products for corn foliar fungicides, soybean foliar and seed-applied fungicides, and wheat foliar fungicides can be found on the Crop Protection Network website.

Mention of specific products in these publications are for your convenience and do not represent an endorsement or criticism. Remember that this is by no means a complete test of all products available.  You are responsible for using pesticides according to the manufacturers current label. Some products listed in the reports referenced above may not actually have an approved Wisconsin pesticide label. Be sure to check with your local extension office or agricultural chemical supplier to be sure the product you would like to use has an approved label.  Follow all label instructions when using any pesticide. Remember the label is the law!