50

Insects and Mites

Wisconsin Pest Bulletin 6/12/14 and 6/19/14 ................. 50

Wisconsin 2014 Pest Management Field Day ................ 50

Plant Disease

Plant Disease Diagnostic Clinic (PDDC) Update ........... 51

Wisconsin Winter Wheat Disease Update for June 19 ... 51

Wisconsin Soybean Disease Update June 19 ................. 52

Fertility and Soil

Potential for Nitrogen Loss Following Heavy

Rainfalls ......................................................................... 53

Crops

Vegetable Crop Update 6/15/14 ..................................... 53

UW Crop Diagnostic Training Center Workshops

for 2014 .......................................................................... 53

Wisconsin Pest Bulletin 6/12/14 and 6/19/14

A new issue of the Wisconsin Pest Bulletin from the

Wisconsin Department of Agriculture, Trade and Consumer

Protection is now available. The Wisconsin Pest Bulletin

provides up-to-date pest population estimates, pest distribution

and development data, pest survey and inspection results, alerts

to new pest finds in the state, and forecasts for Wisconsin’s

most damaging plant pests.

Issue No. 7 of the Wisconsin Pest Bulletin is now available at:

http://datcpservices.wisconsin.gov/pb/pdf/06-12-14.pdf

Issue No. 8 of the Wisconsin Pest Bulletin is now available at:

http://datcpservices.wisconsin.gov/pb/pdf/06-19-14.pdf

Wisconsin Pest Bulletin Site:

http://datcpservices.wisconsin.gov/pb/index.jsp

Wisconsin 2014 Pest Management Field Day

Bryan Jensen, University of Wisconsin IPM Program

Pest Management Field Day

June 26, 2014, 8:30 am

Arlington Agricultural Research Station.

Our field day features several topics presented by University of

Wisconsin faculty, staff and students. Pre-registration is NOT

required and the field day has been accepted for 2.0 CEU in

Pest Management.

Speakers and Topics include:

Environmental Impacts on Soybean Management

Decisions Shawn Conley, UW-Extension/Madison soybean and

small grains specialist, and David Marburger and

Adam Gaspar UW-Madison Department of

Agronomy

Pest Management Mobile Mark Renz, UW-Extension/Madison weed scientist:

Thrips Dispersal and Soybean Vein Necrosis Virus

(SVNV) in Wisconsin Soybean Damon Smith, UW-Extension/Madison plant

pathologist and Chris Bloomingdale, UW-Madison

Department of Plant Pathology:

2014 Alfalfa Fungicide Evaluation Damon Smith, UW-Extension/Madison plant

pathologist:

Soybean White Mold Research Update and

Treatment Evaluation Damon Smith, UW-Extension/Madison plant

pathologist and Jamie Wilbur UW-Madison

Department of Plant Pathology

Herbicide Resistance Research Update for

Wisconsin Palmer Amaranth and Waterhemp

Populations Tommy Butts, UW-Madison Department of

Agronomy

Update on Giant Ragweed Resistance in Wisconsin Dave Stoltenberg and Stacey Marion, UW-Madison

Department of Agronomy:

Volume 21 Number 16 - - - University of Wisconsin Crop Manager - - - June 19, 2014

51

Take Action Against Herbicide Resistance;

Resources and Pigweeds Research Update Liz Bosak, UW-Madison Department of Agronomy

The Value of Transgenic Hybrids in an IPM

Program Joe Lauer, UW-Extension/Madison corn specialist

Tours will leave the Public Events Building promptly at 8:30

a.m. and conclude by noon. In the event of rain, speakers will

present their topics inside the Public Events Building. A light

lunch will be served at the conclusion.

Stay after lunch for a Wisconsin Crop Weed Science (WCWS)

herbicide evaluation results and plot tour. Vince Davis, UW-

Extension weed scientist, with his staff and students will lead

an informal tour of the weed science field research plots.

No preregistration is required and CCA Credits will be applied

for.

The Public Events Facility is located on the Arlington

Agricultural Research Station, N695 Hopkins Road. If

traveling from the south, exit I 90/94 onto Hwy 51 North. Look

for the Arlington Ag. Research Station sign north of Deforest.

Turn left (west) onto Badger Lane. Travel 1 mile and turn left

(south) onto Hopkins Rd. If traveling from the north, exit I

90/94 onto Hwy 60. Travel east through Arlington and turn

south onto Hwy 51. For more detailed driving direction click

on http://www.ars.wisc.edu/arlington/directions.html

Plant Disease Diagnostic Clinic (PDDC) Update

Brian Hudelson, Ann Joy, Joyce Wu, Tom Hinsenkamp, and

Catherine Wendt, Plant Disease Diagnostics Clinic

The PDDC receives samples of many plant and soil samples

from around the state. The following diseases/disorders have

been identified at the PDDC from June 7, 2014 through June

13, 2014.

Plant/Sample Type, Disease/Disorder, Pathogen, County\

FRUIT CROPS,

Apple/Pear, Cytospora Canker, Cytospora sp., Monroe

Apple/Pear, Fire Blight, Erwinia amylovora, Monroe

Strawberry, Root/Crown Rot, Phytophthora sp., Pythium sp.,

Fusarium sp., Cylindrocarpon sp., Chippewa, Wood

VEGETABLES,

Basil, Downy Mildew, Peronospora belbahrii, Dane

Tomato, Gray Mold/Botrytis Blight, Botrytis cinerea, Portage

For additional information on plant diseases and their control,

visit the PDDC website at pddc.wisc.edu.

Wisconsin Winter Wheat Disease Update for June 19, 2014

Damon L. Smith – Extension Field Crops Pathologist,

University of Wisconsin

I have scouted winter wheat fields and variety trials from

Arlington Wisconsin up through Chilton Wisconsin this week,

between rain showers. Wheat in these areas is nearly finished

flowering. The window of opportunity to spray fungicides in

these areas to control Fusarium head blight (scab) in winter

wheat has now passed.

Figure 1 FHB Prediction Center Risk Assessment for June 19

Currently the Fusarium Head Blight Prediction Center

(http://www.wheatscab.psu.edu) is predicting moderate to high

risk for head blight for the Door county peninsula and areas

immediately adjacent to Green Bay (Fig. 1). Winter wheat that

is currently flowering in this area of the state is at high risk for

infection by the fungus that causes scab. The prediction center

is currently predicting low levels of scab in other parts of the

state. This should be monitored closely by growers with barley.

Some late-planted barley will be emerging from the boot soon

and this is the window of opportunity to control scab if

conditions are conducive. With all the rain and warm

temperatures across the state this week, I would suspect that

the risk for scab on barley and any remaining flowering winter

wheat will be elevated this weekend across much of the state.

52

If a fungicide is warranted for control of scab on winter

wheat in the Door County area or barley, products such

Prosaro, Caramba, or similar that contain triazole active

ingredients can offer suppression of scab and reduce

deoxynivalenol (DON) accumulation in harvested grain. These

products should be applied within a week from the beginning

of flowering for reasonable control. Products containing

strobilurin fungicides should be avoided on wheat that has

headed. Research has demonstrated that levels of DON can be

higher after treatment with strobilurin products after heading.

While scouting winter wheat fields at University of

Wisconsin variety trials in the southern and eastern part

of Wisconsin this week, I observed no rust or powdery

mildew. Trace levels of barley yellow dwarf were noted at all

locations. At the Fond du Lac variety trial, high levels of

Cephalosporium stripe (Fig. 2) were noted on certain

varieties. This location has seen short rotations between wheat

crops, likely contributing to this epidemic. We also noted high

incidence (90%) of bacterial leaf blight on several varieties at

this location. Some bacterial leaf streak was also observed, but

incidence was less than 10%. Very low levels of

Stagnospora/Septoria leaf blotch were noted. Most varieties

had just completed flowering at this location and no scab was

observed as of yet.

Figure 2. Cephalosporium Stripe symptoms on Winter Wheat.

At the Chilton Variety trial, diseases are nearly absent. The

only disease noted on several varieties was bacterial mosaic at

low incidence (<5%). Cereal leaf beetle damage was moderate

across many varieties in this trial. Larvae were also found on

flag leaves, but levels were below the economic threshold as of

Tuesday. Again at this location, most varieties had just

completed flowering and no scab was observed as of yet.

Wisconsin Soybean Disease Update June 19, 2014

Damon L. Smith – Extension Field Crops Pathologist,

University of Wisconsin

Soybean planting has finally finished up for our research

program. We planted our last, late planting date trial this

week. Soybeans around the state have emerged and are at the

VC or early V1 stage. Several diseases have been noted

already this year in soybeans.

With all of the rain we have been seeing early symptoms of

Septoria brown spot (Fig. 1). This is a common disease of

soybean in Wisconsin and is caused by the fungus Septoria

glycines. While scouting a field near Fond du Lac this week,

we observed the characteristic purple-brown lesions (Fig. 2)

caused by this fungus, on the unifoliate leaves of soybean

plants. This isn’t unusual considering the moderate

temperatures and frequent heavy rain. The spores of this

fungus are typically rain splashed from old soybean debris, to

the growing plants. Septoria brown spot is usually not

considered a yield limiting disease, but in certain cases, it has

been attributed to significant yield loss. This is usually the

case where a susceptible variety is grown in a location

conducive to the disease and rain is frequent and heavy. In a

situation like this, fungicides might be required during the

reproductive phase of growth to preserve yield. However, most

of the time, Septoria brown spot is observed early in the season

and again late in the season during periods of heavy rainfall

and does not affect yield. I suspect, once the rain subsides a

bit, this disease will also subside. However, growers and

consultants should keep an eye on it just in case it does not. To

learn more about Septoria brown spot, visit the brown spot

information page by clicking here.

Figure 1. Septoria brown spot on a soybean seedling.

Reports of seedling diseases are also starting to roll in as a

result of the very wet conditions and frequent rainfall. Pythium

damping off and root rot is a likely culprit in many of these

53

Follow us on

fields. Cool wet soil conditions at planting and during seedling

emergence favor this disease. There are many species of

Pythium that can infect soybean and soybean pathologists are

currently conducting a study to identify these species. An

informative pocket guide has been developed. You can

download a PDF version of the pocket guide by clicking

here. You will note that management focuses on adjusting

planting date and using seed treatments to protect against

infection by Pythium species. Foliar fungicide application is

NOT recommended for this disease.

Figure 2. Purple-brown lesions characteristic of early Septoria

brown spot symptoms.

Other seed and seedling diseases might also be plaguing

soybeans with all of the wet weather. Other pathogens include

Rhizoctonia and Phytopthora. To learn more about other seed

and seedling issue of soybean in Wisconsin, click here and

scroll down to “seedling diseases.” You will find helpful

resources pertaining to many of the common seedling

issues. Also for specific information on Phytopthora root and

stem rot of soybean, you can download a UWEX fact sheet by

clicking here.

Growers and consultants should scout soybeans for disease

frequently during this cool wet weather. Hopefully the rain

will subside soon. Some dry weather will help slow down the

advancement of many soybean diseases.

Potential for Nitrogen Loss Following Heavy Rainfalls

Carrie Laboski, Soil Fertility/Nutrient Management Extension

Specialist

Some areas in the state have experienced heavy rainfall that has

resulted in water standing in fields. If you are concerned about

potential N loss following heavy rainfall please read:

http://www.npketc.info/?p=180

Flooded Soybean Field

Vegetable Crop Update 6/15/14

The 9th

issue of the Vegetable Crop Update is now available.

This issue contains an Herbicide update - Upbeet for garden

beet, Late blight updates, Blitecast and P-Days for late blight

and early blight management, and information on Basil downy

mildew. Click here to view this update.

UW Crop Diagnostic Training Center Workshops for 2014

Registration is open for UW-Madison Integrated Pest

Management Program’s two Crop Diagnostic Training Center

workshops for 2014. The Diagnostic Troubleshooting

Workshop will be held July 15, 2014. The Crop & Pest

Management Workshop will be held August 5, 2014.

FAST and easy ONLINE registration by credit card:

https://patstore.wisc.edu/ipm/register.asp

Both workshops will be hosted at the Arlington Agricultural

Research Station. Be aware that this is not a ³traditional² field

day. These training sessions are designed to be primarily in-

field and hands-on. We advise that attendees come prepared to

be in the field and ready for all types of weather. CCA CEU¹s

are available as listed, but are subject to change pending

approval from the Certified Crop Advisor Program.

Contact Dan Heider at 608-262-6491, or email

djheider@wisc.edu

To view the flyer for these workshops follow the link below or

scroll down to the end of this newsletter.

http://ipcm.wisc.edu/download/misc/CDTC2014-flyer5.pdf

Diagnostic Troubleshooting WorkshopJuly 15, 2014, Arlington Ag Research StationCCA CEU’s: 4.0 Tiered fee: $75 before 7/1/11, $90 after 7/1/11

● 9:00 Registration and introduction ● 12:00 Lunch (provided) ● 2:15 Adjourn

This Workshop gives you the opportunity to fine tune your crop diagnostic skills in a fun and interactive setting. Small groups will rotate through field problems with UW Specialists role playing as farmers.Through digging up plants, asking questions and con-

sulting references, participants will make a diagnosis of the problem being observed and a recommendation for correction. Each participant will experience eight sepa-rate diagnostic scenarios.

Crop & Pest Management WorkshopAugust 5, 2014, Arlington Ag Research StationCCA CEU’s: 0.5 Crop, 3.5 Pest, 1.0 Nutrient ManagementTiered fee: $75 before 7/25/14, $90 after 7/25/14

● 8:30 Registration and introduction ● 12:00 Lunch (provided) ● 2:45 Adjourn

This workshop will cover agronomic concerns ranging from identification of crop and pest production problems to management options within production systems.

Nutrient uptake and partitioning in soybean - Shawn Conley, Extension Soybean and Small Grains Specialist

● Soybean nutrient requirements effects on the growth and development of high yielding soybeans

Herbicide Mode of Action - Vince Davis, Extension Weed Specialist

● Herbicide mode of action and emerging crop technologies; their use and resistance management strategies

The trait game - Bryan Jensen, UW Integrated Pest Management Specialist

● Management strategies for Bt resistant western corn rootworm; their efficacy and effectiveness in delaying the development of resistance

SCN / SDS Interaction - Damon Smith, Extension Plant Pathology Specialist

● Soybean cyst nematode and sudden death syndrome symptoms; current research on interactions between SCN and the SDS causing fungus

Spray drift mitigation in crop pest management - Daniel Heider, UW Integrated Pest Management Specialist

● Drift reduction, emerging herbicide resistant technologies, nozzles and other drift reduction technology in field settings

Crop Diagnostic Training Workshops 2014UW-Madison Integrated Pest Management Program

Both workshops begin in the Public Events Facility of the Arlington Agricultural Research Station. Be aware that this is not a “traditional” field day. Training sessions are designed to be primarily in-field and hands-on. We advise that you come prepared for all types of weather.

FAST and easy ONLINE registration by credit card: https://patstore.wisc.edu/ipm/register.asp

Contact: Dan Heider, 608-262-6491, djheider@wisc.eduCCA CEU’s are subject to change pending approval from the Certified Crop Advisor Program.