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Record Number Of Scn-Resistant Soybean Varieties Available, More With Peking Resistance, Gregory L. Tylka Oct 2015

Record Number Of Scn-Resistant Soybean Varieties Available, More With Peking Resistance, Gregory L. Tylka

Integrated Crop Management News

The soybean cyst nematode (SCN) reduces soybean yields in every field that it infests. And yield losses can exceed 50 percent when nematode numbers are high and the weather during the growing season is hot and dry. Management of SCN primarily consists of growing nonhost crops, such as corn, in rotation with resistant soybean varieties and using nematode-protectant seed treatments.


Enjoy The Beautiful Fall Weather; Go Sampling For Scn, Gregory L. Tylka Oct 2015

Enjoy The Beautiful Fall Weather; Go Sampling For Scn, Gregory L. Tylka

Integrated Crop Management News

We have had some amazing fall weather so far this year. It is hard to believe that winter is just around the corner. One productive way to enjoy the fall weather, while it lasts, is to collect soil samples to test for the soybean cyst nematode (SCN).


Youth Awarded For Crop-Scouting Skills At 2015 Competition, Daren S. Mueller, Adam Sisson Sep 2015

Youth Awarded For Crop-Scouting Skills At 2015 Competition, Daren S. Mueller, Adam Sisson

Integrated Crop Management News

Farming involves tough questions, such as determining if a fungicide should be applied to corn for northern corn leaf blight, or figuring out if yellow patches in a soybean field are caused by sudden death syndrome, a nutrient deficiency or a different disease. Crop scouting, along with knowing what questions to ask and clues to be on the lookout for, can help determine the right answers to these issues and many others. Educating the next generation of farmers is a goal of Iowa State University’s Integrated Pest Management program.


Why Is All The Corn Dying? Is Anthracnose To Blame?, Alison E. Robertson, Mark A. Licht Sep 2015

Why Is All The Corn Dying? Is Anthracnose To Blame?, Alison E. Robertson, Mark A. Licht

Integrated Crop Management News

The dark green fields that carpeted Iowa’s landscape this summer are very quickly turning brown indicating the end of another growing season. While this color change is not unusual, what is of concern is just how quickly it is occurring. A lot of fingers are being pointed at anthracnose top dieback and/or stalk rot.


A Quality Sample Leads To A Quality Diagnosis, Edward R. Zaworski, Lina M. Rodriguez Salamanca Jul 2015

A Quality Sample Leads To A Quality Diagnosis, Edward R. Zaworski, Lina M. Rodriguez Salamanca

Integrated Crop Management News

The first step in managing a plant or insect problem is to know what is causing the symptoms observed. Accurate pathogen or insect pest identification is one of the most important integrated pest management (IPM) tactics leading to a successful management strategy. So how do you determine what is causing a particular set of symptoms? Sometimes different pests, diseases and disorders cause similar symptoms. How can these be differentiated? One option that many farmers and agribusiness affiliates take advantage of is the Iowa State University Plant and Insect Diagnostic Clinic (PIDC). At the PIDC, we diagnose plant problems, identify insects ...


Soybean Diseases Starting To Pop Up, Daren S. Mueller, Tristan Mueller Jul 2015

Soybean Diseases Starting To Pop Up, Daren S. Mueller, Tristan Mueller

Integrated Crop Management News

This year's early season rain has increased the risk of soybean disease in Iowa. We knew it was coming and now the waiting is over. For the past month we have seen Septoria brown spot and bacterial blight. This week we identified sudden death syndrome (SDS), frogeye leaf spot, and other diseases for the first time this year.


Physoderma Brown Spot And Stalk Rot, Alison E. Robertson Jul 2015

Physoderma Brown Spot And Stalk Rot, Alison E. Robertson

Integrated Crop Management News

Physoderma brown spot and stalk rot is caused by the chytridiomycete Physoderma maydis. This is the only class of fungi that produce zoospores - spores that have a flagellum (tail) and swim in free water. P. maydis survives as sporangia for 2 to 7 years in soil and crop debris. The sporangia are wind dispersed or splashed into the whorls of developing corn plants. When the whorls fill with water for an extended period of time, due to excessive rains or irrigation, the sporangia germinate and produce zoospores that swim and infect the meristematic tissue of the developing plants. Corn is ...


Update On Northern Corn Leaf Blight In Iowa, Alison E. Robertson Jul 2015

Update On Northern Corn Leaf Blight In Iowa, Alison E. Robertson

Integrated Crop Management News

On July 7, 2015, I spent much of the afternoon in Marion Country walking cornfields looking for Northern corn leaf blight (NCLB).

We visited 11 fields planted to various hybrids, and ranging in growth stage from V13 to almost tasseling (VT). Driving up to the fields, the corn looked very good (Figure 1), and it was easy to think there was not much going on in the field.


Hail And Fungicide Use On Corn, Adam Sisson, Daren S. Mueller, Alison E. Robertson Jun 2015

Hail And Fungicide Use On Corn, Adam Sisson, Daren S. Mueller, Alison E. Robertson

Integrated Crop Management News

Hail annually destroys approximately 1.4 percent of corn (Climate of Iowa 2006). Years like 2009 stand out vividly to many people as major hailstorms cut across parts of Iowa, damaging more than 1 million acres of corn in a single season. Many farmers and agronomists have been interested in the effects of fungicide application on corn after a hail event (Figure 1). In response, a multi-year study looking at mid-season "hail events" with fungicides applied after simulated hail events was completed. Here is a videoof the project.


How’S Your Scn Resistance Holding Up?, Gregory L. Tylka Jun 2015

How’S Your Scn Resistance Holding Up?, Gregory L. Tylka

Integrated Crop Management News

If you have fields infested with the soybean cyst nematode (SCN), it is very likely that you are growing SCN-resistant soybean varieties to manage the pest. Resistant soybeans have been a great management tool to combat SCN, but the resistant varieties suffer from a serious lack of genetic diversity.


Diseases Showing Up In Iowa Corn, Alison E. Robertson Jun 2015

Diseases Showing Up In Iowa Corn, Alison E. Robertson

Integrated Crop Management News

Northern corn leaf blight (NCLB) (Figure 1) has been reported from several fields in southern Iowa. You will remember that this disease was widespread in Iowa in 2014, and severe on susceptible hybrids. Since the fungus survives the winter in corn residue, we likely have above normal inoculum present. Cool weather with frequent precipitation favors infection of corn by the fungus and disease development. New lesions may develop every 4 days (Muiro et al., 2010) when conditions are favorable (susceptible hybrid, cool and wet weather). Warm dry conditions will slow or halt disease development until favorable conditions return.


Corn Fungicides: To Spray Or Not To Spray?, Alison E. Robertson, John M. Shriver Jun 2015

Corn Fungicides: To Spray Or Not To Spray?, Alison E. Robertson, John M. Shriver

Integrated Crop Management News

Across the state of Iowa, much of the crop is reaching V5 to V6 and thoughts of an early fungicide application have probably crossed some people’s minds. Every year, we evaluate and compare registered fungicides applied at either V5 to V6, R1 alone, or At V5 to V6 plus R1 for foliar disease management and effects on yield. In 2014, we tested 8 products at 6 locations in Iowa (Table 1). A randomized complete block design with 4 replications was used. At each location, two non-sprayed checks were included.


Get To The Root Of The Problem: An Easy Way To Check For Scn, Gregory L. Tylka Jun 2015

Get To The Root Of The Problem: An Easy Way To Check For Scn, Gregory L. Tylka

Integrated Crop Management News

The soybean cyst nematode (SCN) was first discovered in Iowa more than 35 years ago, in Winnebago County in 1978 to be specific. The nematode is widely considered to be the most damaging pathogen of soybeans in Iowa. Results of random surveys of the state funded by the soybean checkoff and conducted in the mid 1990s and again in the mid 2000s indicate that SCN is likely present in 75 percent or more of Iowa fields. SCN has the potential to increase in numbers very quickly, it can cause 50 percent or greater yield loss, and it can survive dormant ...


Stalk Borers Begin Migration To Corn, Erin W. Hodgson, Adam Sisson May 2015

Stalk Borers Begin Migration To Corn, Erin W. Hodgson, Adam Sisson

Integrated Crop Management News

Degree days are a useful tool to estimate when common stalk borer larvae begin moving into cornfields. Start scouting corn for larvae when 1,300-1,400 degree days (base 41°F) have accumulated. Temperatures have been variable this spring and degree days have been slowly increasing. Southeastern Iowa reached this important temperature benchmark this week (Fig. 1) and therefore scouting for migrating larvae in corn should begin now to make timely treatment decisions. Consider applications at peak larval movement, or 1,400-1,700 degree days (base 41°F).


Soybean Seedling Damage: Is There An Interaction Between The Ilevo Seed Treatment And Pre-Emergence Herbicides?, Kiersten Wise, Daren S. Mueller, Yuba Kandel, Bryan Young, Bill Johnson, Travis Legleiter May 2015

Soybean Seedling Damage: Is There An Interaction Between The Ilevo Seed Treatment And Pre-Emergence Herbicides?, Kiersten Wise, Daren S. Mueller, Yuba Kandel, Bryan Young, Bill Johnson, Travis Legleiter

Integrated Crop Management News

Farmers who were lucky enough to plant soybeans and spray pre-emergence herbicides in between rain events may now be seeing discolored or injured seedlings. Reports of fields with these issues are widespread across Indiana, Iowa, and surrounding areas, and many farmers and crop advisors are questioning if damage is more severe when pre-emergence herbicides are applied to fields that have been planted with seed treated with the new fluopyram fungicide seed treatment ILeVO.


Black Cutworm Moths Captured Throughout Midwest, Erin W. Hodgson, Adam Sisson Apr 2015

Black Cutworm Moths Captured Throughout Midwest, Erin W. Hodgson, Adam Sisson

Integrated Crop Management News

Black cutworm moths (Photo 1) do not overwinter in Iowa and must migrate north annually. Black cutworm moths have been collected in Iowa since the beginning of April 2015. Seeing significant moth captures in early and mid-April is unusual and could indicate a more frequent incidence of vegetative crop injury compared to other years. There have been reports of black cutworm moth trap catches from other states besides Iowa, including Minnesota, Illinois, Indiana, Missouri, and Kentucky. In some places, such as Indiana, peak flights are being reported. A peak flight is a specific number of moths caught in a trap ...


Predicted Mortality Of Bean Leaf Beetle Is Highly Variable, Erin W. Hodgson, Adam Sisson Apr 2015

Predicted Mortality Of Bean Leaf Beetle Is Highly Variable, Erin W. Hodgson, Adam Sisson

Integrated Crop Management News

Bean leaf beetle adults are susceptible to cold weather and most will die when the air temperature falls below 14°F. However, they have adapted to winter by protecting themselves under plant debris and loose soil. Each spring, adult beetles emerge from overwintering habitat and migrate to available host plants, such as alfalfa, tick trefoil and various clovers. As the season progresses, bean leaf beetles move to more preferred hosts, like soybean. Note that while initial adult activity can begin well before soybean emergence, peak abundance can coincide with soybean emergence.


Black Cutworm Monitoring 2015: We Need Your Help!, Adam Sisson Mar 2015

Black Cutworm Monitoring 2015: We Need Your Help!, Adam Sisson

Integrated Crop Management News

Black cutworm moths arrive in Iowa with spring storms each year. These moths lay eggs in fields and the emerging black cutworm larvae cut seedling corn. The sporadic nature of this pest makes scouting essential to determine if management is needed. To make scouting easier, the Integrated Pest Management (IPM) Program at Iowa State University relies on a network of farmers, agronomists, and Extension staff to place and monitor traps for the adult moths (Fig. 1). The IPM Program uses this moth capture data and temperature data to estimate when farmers are most likely to see larvae in their fields.


Evaluation Of Commercial Seed Treatments On Soybean At Three Locations In Iowa In 2014, Mauricio Serrano, Stith N. Wiggs, Alison E. Robertson Feb 2015

Evaluation Of Commercial Seed Treatments On Soybean At Three Locations In Iowa In 2014, Mauricio Serrano, Stith N. Wiggs, Alison E. Robertson

Integrated Crop Management News

With funding provided from Iowa Soybean Association, 15 current commercial seed treatments from 8 companies were tested at 3 locations in Iowa: ISU Northeast Research and Demonstration Farm (NERF) near Nashua; ISU Southeast Research and Demonstration Farm (SERF) near Crawfordsville, and a farmer’s field in Roland (central Iowa). According to recommended maturity groups, public variety IA2094 was planted in Nashua and IA3014 was planted in Roland and Crawfordsville. Replicated plots of 10 feet wide by 17.5 feet long were planted at each location. Seed treatments were professionally applied by the respective companies.


Field Experiments Show Effects Of Clariva™ Seed Treatment In 2014, Gregory L. Tylka, Christopher C. Marett, Alison E. Robertson Feb 2015

Field Experiments Show Effects Of Clariva™ Seed Treatment In 2014, Gregory L. Tylka, Christopher C. Marett, Alison E. Robertson

Integrated Crop Management News

Clariva™ Complete Beans is a seed treatment from Syngenta for management of the soybean cyst nematode (SCN). Clariva Complete Beans contains Clariva™, with the active ingredient Pasteuria nishizawae, a bacterium that parasitizes SCN. Clariva Complete Beans also contains the seed treatment insecticide and fungicides that are in CruiserMaxx® Advanced and Vibrance®.


Evaluation Of Foliar Fungicides And Insecticides On Soybeans In Northeast Iowa, Daren Mueller, Stith Wiggs, Warren Pierson Jan 2015

Evaluation Of Foliar Fungicides And Insecticides On Soybeans In Northeast Iowa, Daren Mueller, Stith Wiggs, Warren Pierson

Iowa State Research Farm Progress Reports

Researchers at Iowa State University assessed fungicide and insecticide applications to soybeans at seven locations across Iowa including the Northwest Farm (Sutherland), Northern Farm (Kanawha), Northeast Farm (Nashua), Agronomy Farm (Boone), Armstrong Farm (Lewis), McNay Farm (Chariton), and Southeast Farm (Crawfordsville) (Figure 1).


Effectiveness Of Foliar Fungicides By Timing On Northern Leaf Blight On Hybrid Corn In Northern Iowa, Alison Robertson, John Shriver, Micah Smidt Jan 2015

Effectiveness Of Foliar Fungicides By Timing On Northern Leaf Blight On Hybrid Corn In Northern Iowa, Alison Robertson, John Shriver, Micah Smidt

Iowa State Research Farm Progress Reports

Fungicide use on hybrid corn has increased considerably, primarily due to reports of increased yields, even in the absence of disease and higher corn prices. A number of fungicides are registered for use on corn. The objectives of this project were to 1) assess the effect of timing of application of fungicides on disease, 2) evaluate the yield response of hybrid corn to foliar fungicide application, and 3) discern differences, if any, between fungicide products.


Strip-Tillage And Row Cover Use In Organically And Conventionally Grown Summer Squash, Jennifer Tillman, Ajay Nair, Jean Batzer, Mark Gleason Jan 2015

Strip-Tillage And Row Cover Use In Organically And Conventionally Grown Summer Squash, Jennifer Tillman, Ajay Nair, Jean Batzer, Mark Gleason

Iowa State Research Farm Progress Reports

Sustainable production of summer squash involves multiple management practices. Some cover crops can be “rolled” when mature to produce a ground-covering mat. The cash crop is then planted in tilled strips made in the residue. This “strip-tillage” technique provides a weed-controlling, moistureretaining mat that is biodegradable, unlike plastic mulches. The reduction in tillage can improve soil health. Row covers provide a favorable microclimate and act as a physical barrier to pests when placed over young transplants. This can help plants grow more rapidly and reduce diseases spread by insects early in the season, such as yellow vine decline and bacterial ...


Effectiveness Of Foliar Fungicides By Timing On Northern Leaf Blight And Common Rust On Hybrid Corn, Alison Robertson, Josh Sievers, Chad Huffman Jan 2015

Effectiveness Of Foliar Fungicides By Timing On Northern Leaf Blight And Common Rust On Hybrid Corn, Alison Robertson, Josh Sievers, Chad Huffman

Iowa State Research Farm Progress Reports

Fungicide use on hybrid corn has increased considerably, primarily due to reports of increased yields, even in the absence of disease and higher corn prices. A number of fungicides are registered for use on corn. The objectives of this project were to 1) assess the effect of timing of application of fungicides on disease, 2) evaluate the yield response of hybrid corn to foliar fungicide application, and 3) discern differences, if any, between fungicide products.


Evaluation Of Foliar Fungicides And Insecticides On Soybeans In Southeast Iowa, Daren Mueller, Stith Wiggs, Warren Pierson Jan 2015

Evaluation Of Foliar Fungicides And Insecticides On Soybeans In Southeast Iowa, Daren Mueller, Stith Wiggs, Warren Pierson

Iowa State Research Farm Progress Reports

Researchers at Iowa State University assessed fungicide and insecticide applications to soybeans at seven locations across Iowa including the Northwest Farm (Sutherland), Northern Farm (Kanawha), Northeast Farm (Nashua), Agronomy Farm (Boone), Armstrong Farm (Lewis), McNay Farm (Chariton), and Southeast Farm (Crawfordsville) (Figure 1).


Strip-Tillage And Row Cover Use In Organically And Conventionally Grown Muskmelon, Jennifer Tillman, Ajay Nair, Jean Batzer, Mark Gleason Jan 2015

Strip-Tillage And Row Cover Use In Organically And Conventionally Grown Muskmelon, Jennifer Tillman, Ajay Nair, Jean Batzer, Mark Gleason

Iowa State Research Farm Progress Reports

Growing muskmelon in a more sustainable way involves multiple management practices. “Rolling” cover crops after they mature, and then tilling strips into which the crops are planted, can help manage weeds and moisture while improving soil health. This “strip-tillage” technique provides a biodegradable mat that does not need to be removed at the season’s end, as plastic mulch does. Row covers are placed over newly planted seedlings to provide a better microclimate and a physical barrier to pests. Extending the time of row cover removal by 10 days after the onset of female flowers has been shown to provide ...


Evaluation Of Foliar Fungicides And Insecticides On Soybeans In Northern Iowa, Daren Mueller, Stith Wiggs, Warren Pierson Jan 2015

Evaluation Of Foliar Fungicides And Insecticides On Soybeans In Northern Iowa, Daren Mueller, Stith Wiggs, Warren Pierson

Iowa State Research Farm Progress Reports

Researchers at Iowa State University assessed fungicide and insecticide applications to soybeans at seven locations across Iowa including the Northwest Farm (Sutherland), Northern Farm (Kanawha), Northeast Farm (Nashua), Agronomy Farm (Boone), Armstrong Farm (Lewis), McNay Farm (Chariton), and Southeast Farm (Crawfordsville) (Figure 1).


Effectiveness Of Foliar Fungicides By Timing On Northern Leaf Blight On Hybrid Corn In Southwest Iowa, Alison Robertson, Bernie Havlovic, Dan Schaben Jan 2015

Effectiveness Of Foliar Fungicides By Timing On Northern Leaf Blight On Hybrid Corn In Southwest Iowa, Alison Robertson, Bernie Havlovic, Dan Schaben

Iowa State Research Farm Progress Reports

Fungicide use on hybrid corn has increased considerably, primarily due to reports of increased yields, even in the absence of disease and higher corn prices. A number of fungicides are registered for use on corn. The objectives of this project were to 1) assess the effect of timing of application of fungicides on disease, 2) evaluate the yield response of hybrid corn to foliar fungicide application, and 3) discern differences, if any, between fungicide products.


Final Year Of Decade-Long National Elm Trial, Jean Batzer, Mark Gleason Jan 2015

Final Year Of Decade-Long National Elm Trial, Jean Batzer, Mark Gleason

Iowa State Research Farm Progress Reports

Although many Dutch elm disease-resistant elm cultivars are available in the nursery trade, much of the public is hesitant to purchase and plant any elm trees. In order to promote interest in planting these trees, scientific data on growth, form, and pest resistance for existing Dutch elm disease resistant elm cultivars are essential.


Evaluation Of Application Rates Of Fungicides On Soybean Diseases And Yield, Shrishal Navi Jan 2015

Evaluation Of Application Rates Of Fungicides On Soybean Diseases And Yield, Shrishal Navi

Iowa State Research Farm Progress Reports

The foliar, stem, and root diseases of soybean are significant components of yield loss in soybean fields. Objectives of this study were to test fungicides against foliar diseases and white mold.