Another CORN DISEASE ALERT: New Bacterial leaf disease ‘Bacterial Stripe’ (Burkholderia andropogonis) of Corn identified in Illinois

Symptomatic corn leaf samples from Champaign County, Illinois have been confirmed positive for the bacterium Burkholderia andropogonis (Pseudomonas adropogonis (Smith) Stapp.) the causal agent of Bacterial Stripe disease by the University of Illinois Plant Clinic. This has been reported to the Illinois Department of Agriculture and the USDA. The pathogen was identified by symptomology, bacterial colony characteristics and  16S DNA sequencing.

Bacterial stripe foliar symptoms unfortunately are similar to other endemic bacterial leaf pathogens of corn, such as Goss’s Wilt and Stewart’s Wilt. Lesions appear initially as lime-green to yellow diffuse discoloration running parallel with leaf veins. As the lesion matures brown necrotic streaking is evident in the center of the lesion, lesions may be 2-5 inches or more in length.

Lesion symptoms of Bacterial leaf stripe on corn in Illinois. Photo credit: University of Illinois Plant Clinic

 

This is a new disease to corn in Illinois. There is little current or historical information available on impact to corn yields by this pathogen in the US. The bacterium is widely prevalent and infects a large number of plants including, Johnson grass, sorghum, rye and clover to name a few. It is reported that the disease becomes more severe during period of wet humid weather. Vidaver and Carlson of the University of Nebraska reported in 1978, that the disease was observed in 1973-1975 in South Dakota, Iowa, Kansas, Nebraska, and Michigan. Conclusions were that the disease caused no economic impact at the time.

Lesion symptoms of Bacterial leaf stripe on corn in Illinois. Photo credit: University of Illinois Plant Clinic

Advanced lesion symptoms of Bacterial leaf stripe on corn in Illinois. Photo credit: University of Illinois Plant Clinic

Be on the outlook for this disease in corn next season. Be aware that symptoms of this disease may be confused with other bacterial leaf blights so lab testing may be necessary to differentiate.


CORN DISEASE ALERT: New Fungal Leaf disease “Tar spot” Phyllachora maydis identified in 3 northern Illinois counties

Tar spot confirmed:  Announced by the Illinois Department of Agriculture today. Corn leaf samples from 3 northern Illinois counties have been confirmed positive for the fungus Phyllachora maydis by Megan Romby National Plant Pathologist with the USDA Animal Plant Health Inspection Service in Beltsville, MD. Positive counties in Illinois are LaSalle, DeKalb and Bureau. The samples were collected from commercial fields by Monsanto breeders and pathologists and sent to Dr. Kiersten Wise in response to her inquiry for samples and distribution information of the Tar spot pathogen. Dr. Wise and Purdue Plant Clinic director Gail Ruhl initially identified the pathogen which is new to the United States 1 ½ weeks ago and submitted confirmation samples to the USDA http://extension.entm.purdue.edu/pestcrop/2015/Issue24/ . Upon receipt of the Illinois samples, they diagnosed the fungus, contacted us at the University of Illinois Plant Clinic and submitted the Illinois samples to the USDA for confirmation at our request.

Scouting for the disease has been active in Illinois. Jennifer Chaky , Pioneer Plant Diagnostic Clinic, also has samples from Bureau County diagnosed with Tar spot and we have additional LaSalle county samples from our University of Illinois Extension Agronomist in Northern IL, Russ Higgins.

Figure 1. Black ascomata of Tar spot on corn leaves in LaSalle County, IL.  Note that orange rust pustules are also present on this leaf.  Photo courtesy of Russ Higgins University of Illinois Extension

Figure 1. Symptoms of Tar spot on corn leaves in LaSalle County, IL. Note that orange rust pustules are also present on this leaf. Photo courtesy of Russ Higgins University of Illinois Extension

Tar spot has distinctive symptoms. The fungal fruiting body, called an ascomata, really does look like a spot of tar on the leaf. Lesions are black, sunken oval to circular. They can be small flecks of about 1/64” up to about 5/64”. The lesions can merge together to produce an affected area up to 3/8”. If you run your finger across the leaf you will feel tiny bumps.

Figure 2. Microscopic view of  fruiting structure of Tar spot from Bureau County, IL.  Photo courtesy of DuPont Pioneer Diagnostician, Jennifer Chaky

Figure 2. Microscopic view of fruiting structure of Tar spot from Bureau County, IL. Photo courtesy of DuPont Pioneer Diagnostician, Jennifer Chaky

 

Prior to the Indiana finding, Tar spot was known to occur only in cool humid areas at high elevations in Latin America. There are actually 2 fungi that cause Tar spot disease on corn Phyllachora maydis and Monographella maydis. While Monographella maydis is known to be able to cause economic yield losses in Latin America, Phyllachora maydis is not known to significantly reduce yield. Other pathogens may be confused with Tar spot, especially the overwintering teliospore (black) phase of corn rust. Also, there are many fungi, called saprophytes that feed on dead corn tissue and form black splotches on the leaves.

To date only one of the pathogens, Phyllachora maydis, has been found in IN and IL. If you suspect Tar spot please submit a sample to the University of Illinois Plant Clinic. We would like to get a comprehensive idea of distribution in the state. For more information on tar spot of corn, please see the USDA-ARS Diagnostic Fact Sheet: http://nt.ars-grin.gov/taxadescriptions/factsheets/index.cfm?thisapp=Phyllachoramaydis


Ewing Demonstration Center Fall Field Day – September 10th

The University of Illinois Extension will host its annual Ewing Demonstration Center Fall Field Day on Thursday, September 10, 2015 at 9:00 a.m.  The Ewing Demonstration Center is located in southern Illinois about 20 miles south of Mt. Vernon at 16132 N. Ewing Rd; Ewing, IL 62836.  It is on the north edge of the village of Ewing, north of the Ewing Grade School on north Ewing Road.  Watch for signs.

The ongoing research this year includes trials on soybean cover crops, nitrogen management in corn, corn maturity, corn seeding rates, soybean seed treatments, and a pumpkin variety trial.

 

The topics to be discussed at Field Day include:

 

Soybean Weed Management

  • Ron Krausz, Manager, SIU Belleville Research Center

2015 Cropping Season Challenges

  • Emerson Nafziger, Extension Crop Specialist, University of Illinois

Planning Ahead for the 2016 Wheat Crop

  • Robert Bellm, Extension Educator, University of Illinois

Results of 2015 Corn and Soybean Insect Surveys: Implications for 2016

  • Mike Gray, Extension Entomologist, University of Illinois

Making the Most of Prevent Plant Acres with Cover Crops

  • Nathan Johanning, Extension Educator, University of Illinois

 

The field day is free and open to anyone interested and lunch will be provided.  Certified Crop Advisor CEUs will also be offered (CM –  1.0, PM – 1.0, SW – 0.5).  For additional information, contact Nathan Johanning (618-687-1727; njohann@illinois.edu) or Marc Lamczyk (618-439-3178; lamczyk@illinois.edu).


Brownstown Agronomy Research Center Field Day – August 5, 2015

The 2015 Brownstown Agronomy Research Center Field Day, presented by the University Of Illinois Department Of Crop Sciences, will be held on Wednesday, August 5. Extension researchers and specialists will address issues pertinent to the current growing season. The tour will start at 8 a.m. and will last approximately three hours. It will be followed by lunch provided by U of I Extension. 2.5 hours of Certified Crop Adviser CEUs have been approved.

Shaded tour wagons will take participants to each stop. These topics will be addressed:

  • 2015 Cropping Season Challenges – Dr. Emerson Nafziger, U of I
  • Weed Management: The Simple Days are Over – Dr. Aaron Hager, U of I
  • Soybean Sudden Death Syndrome – Dr. Angie Peltier, U of I
  • Update on Statewide Insect Surveys & Potential Implications – Dr. Mike Gray, U of I
  • Factors Contributing to a Healthy Soil – Russ Higgins, U of I

The 208-acre Brownstown Agronomy Research Center has been conducting crop research on the claypan soils of southern Illinois since 1937. More than 30 research and demonstration projects are conducted at the Center each year. Visitors are always welcome.

The research center is located south of Brownstown on IL Route 185, approximately 4 miles east of the IL Route 40/185 junction.

For more information, contact Robert Bellm (618-427-3349); rcbellm@illinois.edu
Visit us on the web at http://web.extension.illinois.edu/barc/


Join us in Monmouth on Tuesday, July 28 for the Northwestern Agricultural R&D Center Field Day

The program will begin promptly at 8 am at the Center which is located 1 mile North and 4 miles West of Monmouth at 321 210th Avenue (click here for directions).

Participants will board buses to tour portions of the farm, stopping along the way to visit with University of Illinois personnel who will present results of the most current crop, pest, disease, nitrogen and weed management research.

Certified Crop Advisors may earn up to 2.5 continuing education units.

Topics and speakers will include:

  • Are We Getting Better at Managing Nitrogen? – Emerson Nafziger- Extension Specialist, Crop Production, University of Illinois
  • Management Considerations for Continuous Corn – Brian Mansfield- Research Agronomist, University of Illinois
  • Statewide Insect Surveys: Evidence for Suppression of Key Pests? -Nick Tinsley- Postdoctoral Research Associate, University of Illinois
  • How Compatible are Cover Crops with the Soil Applied Residual Herbicides Used in Corn and Soybean? – Robert Bellm- Extension Educator, Commercial Agriculture, University of Illinois
  • Soybean Sudden Death Syndrome: ID and Management -Angie Peltier- Extension Educator, University of Illinois

For additional information contact Angie Peltier (309) 734-5161, apeltier@illinois.edu.

Click here to download a flier for this event.


Corn disease update and farewell

Last week, I visited all of the University of Illinois corn variety trials in the northern half of the state.  Gray leaf spot and northern leaf blight were beginning to appear in most of the locations, but were the most obvious at the trial located near Perry, IL (Pike County).

DSCN0119

“Young” lesions of northern leaf blight beginning to develop on a corn leaf.

DSCN0128

Gray leaf spot lesions developing on a corn leaf.

With the amount of rainfall received in the past few weeks, it is not surprising that these diseases were beginning to appear.  Since hybrids differ in their level of susceptibility to these diseases, not all hybrids in the trials had symptoms.  If the rainy conditions continue, then a foliar fungicide application sometime between tassel emergence and silking may need to be considered on hybrids that are the most susceptible.  Some general guidelines that may help make a foliar fungicide application decision follow:

  • On susceptible to moderately-susceptible hybrids:  consider a foliar fungicide if disease is present on the third leaf below the ear or higher on 50% of the plants prior to tasseling.
  • On intermediate hybrids:  consider a foliar fungicide if the field has a history of disease, if the previous crop was corn with at least 35% of the ground covered with residue, if disease is present on the third leaf below the ear or higher on 50% of the plants prior to tasseling, and if warm and humid weather has persisted.
  • On moderately-resistant to resistant hybrids:  foliar fungicides generally are not recommended, but scouting is important to confirm that diseases are not present.

The presence of diseases does make a difference in how profitable a fungicide application may or may not be.  From trials conducted at the University of Illinois from 2008 to 2014 at many environments (45 total environments) in Illinois, the results indicate that the overall yield response to foliar fungicides was 5.3 bushels/acre (see chart below).  However, this yield response was 9.5 bushels per acre when disease developed to affect at least 10% of the leaf area in untreated controls (in 17 of the environments).  In situations with low disease severity (disease developed to less than 10% of the leaf area in untreated controls), the average yield response was only 2.8 bushels per acre (in 28 of the environments).  Obviously, the marketing price of corn and the fungicide and application costs will determine if fungicide applications were profitable.  The chart below shows the profitability of fungicide applications under different yield response goals (3, 5, 8, and 11 bushels per acre).  The bottom line is that it takes a higher yield response to be profitable when corn marketing prices are lower.

Corn fung results 2014

Results from University of Illinois corn fungicide trials conducted from 2008 to 2014. All applications were made at tassel emergence (VT).

On a final note, my last day at the University of Illinois is today (June 30).  I will be moving to a similar position at the University of Kentucky, and will be based out of the Princeton Research and Education Center in the western part of Kentucky.  I want to thank the University of Illinois for my opportunities here and thank many of you for your support and interest.  There are no current plans to replace my position as Extension Plant Pathologist at the University of Illinois.  If you have field crop disease questions, the following contacts may be useful:

University of Illinois Plant Clinic

1102 S. Goodwin Ave.

Urbana, IL 61801

Tel: 217-333-0519

Email: plantclinic@illinois.edu

 

Commercial Agriculture Extension Educators:

Robert Bellm

Brownstown Agronomy Research Center

1588 IL 185

Brownstown, IL 62418

Tel: 618-427-3349

Email: rcbellm@illinois.edu

 

Dennis Bowman

Crop Sciences Research and Education Center

1102 S. Goodwin Ave.

Urbana, IL 61801

Tel: 217-244-0851

Email: ndbowman@illinois.edu

 

Russ Higgins

Northern Illinois Agronomy Research Center

14509 University Road

Shabbona, IL 60550

Tel: 815-824-2029

Email: rahiggin@illinois.edu

 

Angie Peltier

1000 North Main Street

PO Box 227

Monmouth, IL 61462

Tel: 309-734-5161

Email: apeltier@illinois.edu


Spring Cover Crop Field Day March 26th – Ewing Demonstration Center

Join us on Thursday, March 26th, 2015 for the  Spring Cover Crop Field Day at the University of Illinois Extension Ewing Demonstration Center.  Registration will start at 8:30 a.m. and the program will begin at 9:00 a.m., rain or shine.  The Ewing Demonstration Center is located at 16132 N. Ewing Rd; Ewing, IL 62836, on the north edge of the village of Ewing, north of the Ewing Grade School on north Ewing Road.  Watch for signs.

Cover crops have many benefits to the soil, environment, and overall crop production and management.  Topics covered during this field day program include:

Challenges of Grazing Lush Spring Forage

–          Travis Meteer, Extension Educator, U of I Extension

Techniques for Planting into Cover Crop Residue

–          Mike Plumer, Private Consultant

Understanding the Soil Profile Beneath Your Feet

–          Bryan Fitch, Resource Soil Scientist, NRCS

Which One to Choose? Cover Crop Species Selection and Demonstration Trial Tour

–          Nathan Johanning, Extension Educator, U of I Extension

Some of the program highlights will be the demonstration trial planting of cover crops, including 17 different cover crops and combinations illustrating first hand the characteristics of the cover crops and what benefits they bring to your soil and crop production system.  Also, (weather and soil conditions permitting) we will have a soil pit dug, exposing the soil profile, where NRCS Resource Soil Scientist, Bryan Fitch will lead us through the characteristics of our southern Illinois soils to enhance understanding of the importance of a healthy soil.  Also Certified Crop Advisor CEU credits will be available (2.0 Soil & Water Management & 1.0 Crop Management) for the program.

This field day will be free and open to anyone interested in learning more about cover crops.  A light lunch will be provided and this is a great way to talk to fellow growers to learn more from their challenges and successes incorporating cover crops into their cropping systems.  Please call the Franklin County Extension Office at 618-439-3178 for more information and to register by March 24th.  We hope to see you there!


Dates and Locations for the 2015 University of Illinois Corn & Soybean Classics

The dates and locations for the January 2015 University of Illinois Corn & Soybean Classics are set.  Our next series of meetings marks the 18th year of the Classics and will continue the program’s tradition of providing our clientele with the most current and timely information related to crop production, marketing and pest management.

The dates and meeting locations for the 2015 Corn & Soybean Classics are:

▸ January 7 (Wednesday): Peoria Par-A-Dice Hotel

▸ January 8 (Thursday): Moline i wireless Center

▸ January 9 (Friday): Malta Kishwaukee College

▸ January 12 (Monday): Springfield Crowne Plaza

▸ January 13 (Tuesday): Champaign I Hotel and Conference Center

▸ January 14 (Wednesday): Mt. Vernon Holiday Inn

Please mark your calendar and plan to join us at one of these locations.  We will provide additional information related to the program in a future issue of the Bulletin.

 


2014 Ewing Demonstration Center Fall Field Day

2014 Ewing Demonstration Center Fall Field Day

The University of Illinois Extension will host its annual Ewing Demonstration Center Fall Field Day on Thursday, September 11, 2014 at 9 a.m.  The Ewing Demonstration Center at is located at 16132 N. Ewing Rd; Ewing IL 62836, on the north edge of the village of Ewing, north of the Ewing Grade School on north Ewing Road.  Watch for signs.

The ongoing research plots this year consist of a soybean cover crops trial, LibertyLink soybean variety trial, insecticide/fungicide trial on soybeans, corn population study, drought tolerant corn hybrid evaluation, and new this year a pumpkin variety trial.

 

The topics to be discussed at Field Day include:

Fusarium Head Blight (Scab) and Vomitoxin Management in Wheat

  • Carl Bradley, Extension Specialist, Plant Pathology, University of Illinois Extension

Sky High Crop Scouting; Unmanned Aerial Drones

  • Dennis Bowman, Extension Educator, University of Illinois Extension

Alternative Forages and Harvesting Methods

  • Teresa Steckler, Extension Educator, Commercial Ag, University of Illinois Extension

Palmer Amaranth: Coming (Soon) to a Field Near You

  • Robert Bellm, Extension Educator, Commercial Ag, University of Illinois Extension

Cover Crops and Weed Management

  • Nathan Johanning, Extension Educator, Small Farms Local Foods, University of Illinois Extension

Refreshments will be provided by Franklin County Farm Bureau.

The field day is free and open to anyone interested.  A light lunch will be provided and registration is recommended by September 8, 2014 for an accurate meal count.

For additional information or to register, contact Marc Lamczyk at University of Illinois Extension Office in Franklin County at 618-439-3178 or lamczyk@illinois.edu.

 


2014 Field Day August 7 at Dixon Springs Ag Center

The 2014 Dixon Springs Agronomy and Horticulture Field Day presented by the University of Illinois, Department of Crop Sciences will be held on Thursday, August 7 at the Dixon Springs Ag Center.  The research center is located on IL Route 145, near Glendale, IL, 25 miles south of Harrisburg and 25 miles north of Paducah, KY.

Tours will start at 9:00 AM with the final bus leaving at 9:30. A lunch to follow will be provided by sponsors and UI Extension.

The following presenters will speak about current conditions and management challenges in field crop and horticulture production.

  • Carl Bradley: Fungicide Resistance
  • Angie Peltier: Corn Nematodes, The Hidden Menace in Your Fields
  • Jake Vossenkemper: Nitrogen on Soybeans
  • Rachel Cook: Tillage is Recreational, Fertilizer is Essential: A 44 Year Study
  • Jeff Kindhart: High Tunnels, Hydroponics and Mushrooms

For more information contact John Pike at 618-695-2441 or by email at jpike@illinois.edu