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Corn Newsletter : 2019-06
Soybean Cyst Nematode Samples – Spring is still a good time!Author(s): Anne Dorrance
Lots of news about Soybean cyst nematode at Commodity Classic a couple of weeks ago. We have continued support to run assays and education sessions for farmers throughout the region to be able to answer “What’s your number?” There are fields throughout the Midwest, where not only are SCN numbers creeping up to economic levels but also the reproduction factor, which is the ability to reproduce on the one source of resistance (PI 88788) is also creeping up. The good news is that adaptation to the PI 88788 type of resistance towards SCN in soybean is going to be slow – but it is happening in a couple of fields in Ohio where the number of cysts are up to 27% of the susceptible check.
We received soil samples from 238 fields during 2018 – here is the breakdown.
SCN Population Level
% of total
High (5000 +)
The highest counts to date are approximately 15,000 eggs per 100 cc of soil.
So here is the challenge – we are missing samples from some regions of Ohio and definitely could use some more soil samples from all counties. Here is the breakdown by county.
# Fields sampled
# Fields sampled
# Fields sampled
Once the samples are processed, those with >500 eggs per 100cc are then added to the pipeline to evaluate for which source of resistance is effective towards that population: PI 88788 or Peking. This will help first, the farmer to know what type of seed to buy and second companies to make decisions on what type of SCN resistant trait to target for Ohio soils. So help us have the best data set in the US by sampling today.
How to sample – there are lots of you tube videos on this from my extension colleagues throughout the region, and Ohio State is no exception. One of our former Ph.D. students, who earned his degree studying soybean cyst nematode produced this piece:
And here are my specific suggestions of where to sample to find SCN:
1. Review the yield maps and target those areas of the field where yields were low and you can’t explain why. No flooding or weed outbreak.
2. Target fields with heavy purple dead nettle or other winter annuals that can SCN can reproduce on, especially during a warm winter.
3. Target fields that are planted continuously to soybean or those where rotations are rare. Don’t forget double crop situations in these fields. For full season soybeans, we can have 3 to 4 life cycles per growing season depending on where your fields are in the state, with double crop soybean, there is time for at least 2 life cycles, thus almost negating the effect of planting a non-host, where the populations can drop by 50%.
Members of the American soybean Association were sent sample bags last May. And if you are like me, it is probably still on your desk, so please take a look for that. If you are not a member, let your county educator know – we will be shipping bags to each county educator in the next few weeks.
Information to supply when submitting a soil sample for SCN processing
For more information- check out our SCN information at:
SCN Coalition: https://www.thescncoalition.com/
Late season rains impacted seed qualityAuthor(s): Anne Dorrance
Co-author: Felipe F. Sartori, Ohio State Department of Plant Pathology
Lots of calls and samples concerning seed quality (Figure 1) and I’ve also heard about the rejections at the elevators. I was in Florida a couple of weeks ago with my colleagues (soybean pathologists) from across the country and Ontario, Canada and we are not alone. We were not the only state whose soybeans had plentiful rains through and after grain fill with some still in the field!
What is causing all of the low germination? From the samples we have received, we are culturing the expected seed borne pathogens: Phomopsis, Diaporthe, Fusarium, and Cercospora spp. (Figure 2, 3) All of these will affect seed and seedling health if the seed is not treated with a fungicide that can control true fungi.
What types of fungicides are there? On the seed, there are materials to control the watermolds (Pythium and Phytophthora), insects, SCN, and the true fungi Phomopsis and Fusarium. There is one seed treatment which only targets the SDS pathogen, Fusarium viruguliforme. Refer to the fungicide seed treatment table https://u.osu.edu/osusoybeandisease/management/
Is it worth treating the seed? In the old days, the recommendations were if you has a batch of seed that was less than 70% germination, that it should not be used the next year. Based on the samples we received, the infections were mostly on the outside of the seed and the seed germinated before it was colonized by the fungus. Seed treatments greatly improved germination and health of the seedling by as much as 40 to 50%. We have stored the seed under very dry conditions, to inhibit any additional colonization of the seed, so that has helped. With seed of some varieties going to be limited, and the seed treatments are working, we may have some room here if needed, but only the best soybeans should be used for seed.
Which fungicide seed treatment was most effective? There are several fungicide active ingredients that are effective towards Phomopsis and Fusarium seed decay: fludioxonil, fluzapyroxad, ipconazole, PCNB, penflufen, prothioconazole, pyraclostrobin, sedaxane, and thiabendazole (TBZ). Thank you to Syngenta Crop Protection and Valent, we were able to evaluate a couple of these compounds on some poor quality seed. Fungicide seed treatments (rate per cwt) that we evaluated were: 1) nontreated control; 2) thiabendazole 0.08; 3) thiabendazole at 0.16; 4) fludioxonil 0.08; 5) fludioxonil 0.16; and 6) thiabendazole 0.08 plus fludioxonil 0.08.
Interestingly, fludioxonil was not effective on one of the seed lots, as was ipconazole in another study (data not shown). But the combination of fludioxonil plus thiabendazole provided the most consistent increase in germination over the nontreated across the seed lots (Figure 4). Bars with a letter that are same are not significantly different within each seed lot. The primary reason for these difference is that each seed lot was infected with a slightly different group of seed borne pathogens.
Pick the best conditions to plant in 2019! Soybean seed had a rough go of it at the end of the 2018 season and it will also have a rough go of it once it is planted. Once it is cleaned and sorted, has the right fungicide seed treatment on it, use the best days to plant the seed. As close to that May 1 day where soil temps (not air temps) are suitable and the rain that is forecast is reasonable, not an Ohio 4 to 5” dump like we’ve been getting. My fingers are crossed, we have a decent planting season this year.. we are long overdue!
Dragline application of manure to growing soybeans
As we continue to search for profitable ways to expand the manure application window in Ohio, we have begun to research dragline application of manure to growing soybeans. While this would potentially open up more time for manure application in the spring, our initial research goal is to look at the ability to apply manure to emerged double crop soybeans after wheat. For many years, livestock producers have successfully applied liquid manure to newly planted soybeans in July to help provide moisture for germination and emergence.
In 2018 we conducted trials at Western and Northwest OARDC to determine the yield effects a loaded 5 inch drag hose would have on growing soybeans. Plots were 30 feet wide and 90 to 2000 feet long. Plots were harvested with a small plot combine with a two-meter head allowing us to look at damage caused by the drag hose versus damage caused by the tractor tires. At every growth stage wheel damage was evident, with a trend of lower yields in the center where wheels were. It may be beneficial to use tracks or at least a non-dualed tractor to minimize wheel damage. A five inch loaded drag hose was utilized in the study and each plot was drug once to best represent real field damage. Each location had either two or four replications and also had an untreated check.
Full plot averages at OARDC Northwest (2 replications)
Treatment growth stage
Plot Average (bu/acre)
Significant LSD= 6.33
Full plot averages at OARDC Western (4 replications)
Treatment growth stage
Check full width
V3 full width
V5 full width
V7 full width
Both locations saw minimal visual damage from the dragline at soybean growth stages through V3. At the V5 stage there was a noticeable curve to many of the soybean plants. At the V7 stage, most of the soybean plants were partially broken off at the ground level but continued to grow and produce pods. None of the replications had treatments statistically different than the untreated check. Both sites had plentiful rainfall in the months of July, August and September. This moisture may have masked yield damage from the drag hose. Soybeans had plenty of moisture to recover from damage by putting out more branches.
Yearly precipitation summary for OARDC Western and Northwest
It is important to remember that no manure was applied to the soybeans, which we will focus on in the coming years. We know that manure may have a high enough salt content to kill soybeans. In previous field trials, we have seen instances where banded manure before soybean planting killed the soybeans in those strips.
Work done by the University of Nebraska looking at using manure through a center pivot irrigation system studied how salt content of the manure effects soybeans. This study looked at applying a half-inch (13,577 gallons) of manure at the V3 or R1 growth stage. Electrical Conductivity (EC) was used to tell how much salt was in 2728 samples of liquid swine, dairy, and beef manure from covered and open lagoons. Manure from under a swine finishing barn had an EC was 20.3 decisiemens per meter (ds m-1) and was used as the base manure for all treatments and diluted with water for lower EC treatments.
Seventy five percent of the samples had an EC of 11.7 ds m-1 or less. The treatment with an EC of 20.3 saw a significant decrease in soybean yields compared to all other treatments. Treatment with an EC of 11.7 and all treatments below this level had similar soybean yields. Plots showed foliar necrosis at the 11.7 EC treatment and plants were shorter than lower EC treatments but yield was not affected by this damage. Prior research has shown an EC salt threshold of 6.4 ds m-1 for soybeans at the V3 growth stage and younger. Gallons per acre and weather conditions can greatly affect the damage done to soybeans from manure application.
When combining these two studies it will be important to have a current manure analysis to know the EC or salt content of the manure. Especially with manure from under barn, swine storage facilities. The higher the nitrogen and potassium level, the higher the salt content. The study on drag hose damage shows that soybeans can handle incredible stress, the real test will be to combine the two stress factors. Over the next couple of years, we will continue the work on the potential to dragline soybeans with liquid manure looking at both damage from the drag hose and the manure itself.
The authors wish to thank the Ohio Soybean Association for sponsoring this research.
C. A. Shapiro, W. L. Kranz, C. S. Wortmann. 2005. Salt thresholds for liquid manure applied to corn and soybean.
Fertilizer License and Poultry LitterAuthor(s): Glen Arnold, CCA
There have been a few phone calls from farmers calling about needing to get their fertilizer license in order to receive or spread poultry litter. This has been the law in Ohio for several years since Senate Bill 1 was passed. Any farmer handling, receiving, or applying poultry litter (or any other manure) from a permitted farm in Ohio must have either a fertilizer license or a Certified Livestock Manager certificate or be a Certified Crop Advisor. Most poultry farms in Ohio are permitted so nearly all the poultry litter available to farmers is from permitted farms.
If you need new fertilizer license certification there are still a few opportunities in March and April. Here is a website you can access for dates and locations.
First Time Fertilizer Certification Class - Auglaize/Shelby Counties - March 25th
Have you gotten your Fertilizer Applicator Certification, yet? Do you apply fertilizer to more than 50 acres of crops that you sell? Do you side-dress your corn and farm more than 50 acres? Yes, that last point could be the “tipper”! Even if you farm only 50 acres and usually split that across two or three crops, what about the year – for whatever reason – that you plant all corn?? Yep, when it’s time to side-dress that corn, you’re “got”!!
You do have a few options: 1) Hire someone else to do it. 2) Take a test to get your certification. 3) Join us on Monday, March 25th for the three-hour Fertilizer Applicator Certification Training . . . and avoid any test! We’ll even give you a choice of two sessions!
Auglaize and Shelby County Extensions will be holding this Fertilizer Applicator Certification course at the Palazzo, 309 W. Main Street, Botkins (between exits 102 and 104 off I-75) on March 25th. You can choose from 2 p.m.-5 p.m. or 6:15 p.m.-9:15 p.m. and there will be a light supper available between those two sessions. The cost is $30 for the training. Instructors will be Jeff Stachler (email@example.com) and Debbie Brown (firstname.lastname@example.org). Contact either one of us to get signed up!
First Time Fertilizer Certification Class - Tuscarawas Co. - April 9thAuthor(s): Chris Zoller
Do you apply fertilizer (other than manure) to more than 50 acres of land on crops grown primarily for sale? If so, the Ohio Department of Agriculture requires that you complete a three-hour fertilizer certification training. Even if you apply fertilizer to less than 50 acres and/or feed all of your crops to livestock, you are encouraged to become certified. The Tuscarawas County office of Ohio State University Extension will conduct a fertilizer certification class for anyone who is not certified. This is NOT for recertification. The training will be held April 9 at 7 pm at the Community Center in the Village of Tuscarawas at 222 E. Cherry St.
Please contact the Tuscarawas County office of Ohio State University Extension at 330-339-2337 no later than April 5 to pre-register. Additional information is available at http://tuscarawas.osu.edu.
About the C.O.R.N. Newsletter
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.
The information presented here, along with any trade names used, is supplied with the understanding that no discrimination is intended and no endorsement is made by Ohio State University Extension is implied. Although every attempt is made to produce information that is complete, timely, and accurate, the pesticide user bears responsibility of consulting the pesticide label and adhering to those directions.
CFAES provides research and related educational programs to clientele on a nondiscriminatory basis. For more information, visit cfaesdiversity.osu.edu. For an accessible format of this publication, visit cfaes.osu.edu/accessibility.