CFAES Give Today
Agronomic Crops Network

Ohio State University Extension


C.O.R.N. Newsletter 2006-01

Dates Covered: 
January 10, 2006 - January 24, 2006
Harold Watters

2006 Crop Profit Program January 18, 6:00 pm - 7:30 pm

Authors: Harold Watters

Soybean Rust- The 2005 Experience and 2006 Management??
• Identification and Development of Soybean Rust from the Southern Experience- Dr Ed Sikora, Dept. of Plant Pathology, Auburn University ?
• Ohio Soybean Rust Management for 2006- Dr Anne Dorrance, Dept. of Plant Pathology, Ohio State University

These broadcasts, hosted by Dale Minyo of ABN Radio, will highlight current production practices, input recommendations, and economic concerns for Ohio's agronomic crop industry. Farmers, agronomy retailers, agribusinesses, CCA's, and anyone interested in agriculture will find important recommendations for the upcoming year. Our first broadcast of 2006 will be on January 18th beginning at 6p.m.
Broadcast via web to participating locations coordinated by our County Extension Offices, see for more information on sites. The list below shows locations as of this date.

Union County Agricultural Center
18000 St.Rt. 4 Suite E

OSU Extension-Morrow County
871 W Marion Road
Mt. Gilead

Champaign County Community Center
1512 South US 68

OSU Extension
117 E. Mansfield Street

Clinton County Extension Community Room
111 S. Nelson Ave

Miami County Extension Office
201 W. Main St.

OSU Extension
810 Fair Road

Ashland County Agriculture and Family Center (downstairs meeting room)
804 US Hwy 250 East

OSU Extension, Auglaize County
208 S. Blackhoof Street

Hancock Co. Ext. Office
7868 CR 140

OSU Extension, Darke County Office
603 Wagner Ave.

OSU Extension
2000 Countryside Drive

Stark County Extension Office
2650 Richville Drive SE

Van Wert County Extension Office
1055 South Washington
Van Wert

Lorain Co. Ag. Center
42110 Russia Road

Robert Fulton Ag Center
8770 St Rt 108

OSU Extension Williams
1122 W High St

Ashtabula County Extension Office
39 Wall Street

Standing Water in Wheat Fields

Authors: Pierce Paul, Jim Beuerlein, Dennis Mills

Standing water in wheat fields may or may not have a negative effect on the wheat crop. During dormancy, standing water has little or no effect on the plants. However, as spring approaches and the wheat plants come out of dormancy, poorly drained or flooded soils negatively affect root aeration and the availability and utilization of soil nutrients. Plants deprived of oxygen and nutrients may not survive or may become debilitated and predisposed to pest and disease problems. During winter dormancy, the metabolism of the plant is greatly reduced, and as such, the demand for oxygen is very low. However, as temperature increases, plants become metabolically active and the demand for food and oxygen increases. Hence, the length of time the plants can survive standing water depends on their metabolic activity. Wheat plants are better able to survive flooding during the winter when they are dormant than during early spring when dormancy is broken.

In addition to affecting air and nutrient availability, excess soil moisture keeps soil temperatures low and increases relative humidity. These conditions favor the occurrence of root and lower stem disease problems. Weakened and flood-stressed plants growing under conditions favorable for development of disease-causing organisms are easily infected and may become diseased. Even weakly pathogenic organisms may infect and cause disease in stressed plants. Whereas winter temperatures are generally unfavorable for pathogen growth and development, pathogen activity increases as temperature increases. Some soilborne pathogens thrive under conditions of relatively cool temperatures, high relative humidity, and wet soils. Pathogen infection may lead to root rots and seedling blights, leaving plants stunted with poorly developed roots and tillers. When fields remain waterlogged for extended periods during late winter and early spring, plant death is often the result of a combination of poor aeration, poor nutrition, and pathogen infection.

Soybeans: How to Minimize Losses Due to Diseases During 2006

Authors: Anne Dorrance

Ohio conditions favor many soybean pathogens including seedling and root rots, soybean cyst nematode and Phytophthora root rot. During 2005 we also witnessed numerous foliar diseases, frogeye leaf spot, brown spot and downy mildew.... Fortunately no soybean rust was found. There are numerous things that producers can do to minimize effects for these diseases and prepare for soybean rust during 2006.

1) Variety selection. Disease management starts with good variety selection. Choose varieties that have the best resistance package for your fields.

For Phytophthora choose a variety with Rps1c, Rps1k or Rps3 gene BUT also be sure that the partial resistance level (tolerance) is high. For the Ohio Performance Trials we use a scoring system of 1 to 9 – 3 is generally our best score and 9 is dead. Not all of the companies use the same scoring system so be sure to read the fine print when choosing varieties. In our studies, a resistance gene is only effective for about one half the population in any given field so the partial resistance is important to provide the “safety net”.

For SCN – monitor SCN populations in fields to determine what the levels are – then choose a variety based on that. If no or low SCN populations are present, then choose other varieties, do not plant a SCN resistant line in that field. For low to moderate levels, choose a SCN resistant line, sources of resistance are PI88788, Hartwig or CystX. For fields where PI88788 has been used for several years, monitor these fields, there are reports of SCN reproducing on these varieties. This is to be expected as all current sources of resistance do have some SCN somewhere in the US that can reproduce on these soybeans.

2) Seed Treatment. For those fields where replant has been an issue in the past, poor drainage, continuous soybeans or short rotations, a seed treatment will give an economic return more often than not. For those fields with a history of Phytophthora – use the highest labeled rate of Allegiance (1.5 fl oz/cwt) or Apron XL (0.64 fl oz/cwt) to get the best protection.

Improve drainage. All of the root rots, especially Phytophthora, require very moist to flooded soil conditions to cause disease. Improving soil drainage from tillage to replacing drain tiles reduces the time the fields are saturated, thus reducing the time these pathogens can infect roots.

Crop rotation – this is still one of the most effective disease management strategies for soybean cyst nematode. Every year that soybeans are not planted in a field reduces the SCN population by one half.

Northwest Ohio 2005 Soybean Aphid Season Analysis

Authors: Alan Sundermeier

Agents in Northwest Ohio focused on quantifying the distribution of soybean aphid in the area during the 2005 growing season. A speed sampling technique was tested for accuracy.

Scouting was conducted in the counties of Wood, Henry, Fulton, VanWert, Crawford, and Allen. Several fields in each county were scouted weekly from the first signs of aphids until pesticide spraying. A total of 49 fields were used to collect data. Up to 20 sites were selected in each field. These sites were GPS located whenever possible and observations were gathered from that specific site each week. In this way, field variation was overcome by tracking an exact site’s aphid changes over time.

As predicted, soybean aphids were a widespread problem in the summer of 2005 with every participating county reporting above threshold levels by August.

Movement spread from northern counties of Wood, Fulton, and Henry reporting initial soybean aphid counts during the week of June 27. Crawford and VanWert counties did not report initial counts until the week of July 18 or later. It took about 3 weeks for a site to increase from just a handful of aphids per plant to over threshold of 250 aphids per plant. The period of July 25 to August 7 saw a majority of Northwest Ohio fields applying pesticide control for soybean aphids.

Distribution of soybean aphids within an individual field site did not vary significantly. The speed sampling technique developed by the University of Minnesota was tested and proved to be a good model, refer to their web site for more details When every soybean plant counted had at least 40 or more aphids per plant, threshold levels were reached and a pesticide application was needed. This technique will save time for scouting and still accurately predict treatment needs.

Because of the variation of infestation timing in the area, there will continue to be a need to gather localized aphid population data to accurately determine if a pesticide application in needed. Weekly observations are needed once an initial infestation has been detected. Speed sampling scouting may be used to allow a rapid assessment of a site to determine threshold levels.

Certified Livestock Managers Training, Feb 1-2, 2006

Authors: Harold Watters

Manure from large livestock and poultry farms can be an asset when handled properly as a fertilizer. It can also be the largest liability for a farm if handled incorrectly. The Ohio Department of Agriculture is sponsoring a Certified Livestock Manager Training Session for any farmer or custom applicator who needs to get licensed by ODA or who wants to learn more about best management practices concerning manure management.

This two-day event is to be held at the OSUE Union County office, Marysville Ohio. See this site for on-line access to the program brochure: You may also contact Kelly Harvey at 614 387-0908 for more information. The registration deadline is January 23rd.

Archive Issue Contributors: 

Peter Thomison (Corn Production), Anne Dorrance, Pierce Paul, and Dennis Mills (Plant Pathology), Jim Beuerlein (Soybean & Small Grain Production) and Jeff Stachler (Weed Science). Extension Agents: Ed Lentz (Seneca), Dusty Sonnenberg (Henry), Gary Wilson (Hancock), Howard Siegrist (Licking), Harold Watters (Champaign), Steve Prochaska (Crawford), Mark Keonig (Sandusky), Alan Sundermeier (Wood), Bruce Clevenger (Defiance) and Greg LaBarge (Fulton).

Crop Observation and Recommendation Network

C.O.R.N. Newsletter is a summary of crop observations, related information, and appropriate recommendations for Ohio crop producers and industry. C.O.R.N. Newsletter is produced by the Ohio State University Extension Agronomy Team, state specialists at The Ohio State University and the Ohio Agricultural Research and Development Center (OARDC). C.O.R.N. Newsletter questions are directed to Extension and OARDC state specialists and associates at Ohio State.