Dr. Anne Dorrance is well known across Ohio and the country as a leading soybean disease researcher and excellent teacher. As an Ohio State University Extension plant pathologist, she is a regular contributor to the Crop Observation and Recommendation Network aka C.O.R.N. Newsletter. Recently she shared insight that could help farmers increase yields and improve the quality of soybean delivered to the market. Believe it or not, she and I have some lively discussions about soybean disease management and although she usually wins, I occasionally enlighten her.

•If a variety performed poorly in 2009 let that dog go. We are now looking at higher inoculum levels of many pathogens going into 2010. So it is time to re-evaluate some of our production systems. Rotation and tillage are the best management strategies for knocking back pathogen inoculum be it from SCN, foliar diseases, Sclerotinia or Phomopsis on seed. You have two choices: get out of that field or put some dirt on it - the best response for an outbreak might be to do both. Bender perspective: Rotation … definitely, tillage … maybe, but we should avoid erosive fields. Our best long-term no-tillers produce profitable soybean crops.

•Choose varieties with the best disease resistance package for your farm. Pick a variety that has high levels of partial resistance to Phytophthora plus either Rps1c, Rps1k or Rps3 or a combo; good Frogeye, and SDS ratings. For those historic Sclerotinia fields, it must also have a Sclerotinia rating. For SCN put the SCN resistant lines on those fields with 200 to 2,000 or more eggs/cup of soil but avoid severe problem fields.

•Don’t push the planting. If it is wet or the forecast says a whopper of storm is on the way, go to the coffee shop. Do not try to get it in. A pounding rain frequently results in replanting the field. Also, don’t mud it in. More often than not you are looking at a replant situation. Bender experience: Been there, done that.

•Use treated seed. When our clay and clay loam soils get wet, they hold water for 24 to 48 hours, which is just perfect for the water molds and other fungi that love to attack young seedlings. Be sure you have the best rate for Phytophthora, something in there to cover the fungi (Fusarium, Rhizoctonia, and seed borne Phomopsis and Sclerotinia) and then follow the information for insecticides. Bender note: Seed treatments are well worth the investment.
•Rotate. If you had a poor return on a crop in a field last year don’t put it in again. It is time to explore other options.

•The fall was a bit wet for SCN sampling. If we have a long dry spring and you can pull them in April - do it. Spring counts are better than no counts at all in fields where SDS was observed and/or SCN is suspected.

•If something did not work figure out why. We should learn more from what did not work than what did at times. If you were applying a fungicide did you get it on in time; did it go where you needed it to go or did it sit on top of the canopy; was it the right material or was it even necessary?

The two most important decisions you will make are matching the right variety genetics to each field. Take your time, look at the field histories and get it all planned out now if you have not already done so.

Dr. Dorrance gives her best wishes for a bumper crop in 2010. I totally agree.

The opinions expressed in this column are those of the author and not necessarily those of Farm World. Readers with comments for Roger Bender may write to him in care of this publication.