Q&A KEY QUESTIONS Bayer CropScience Corporate Communications 2 TW Alexander Drive Research Triangle Park, NC 27709 Tel. 919-549-2000 ILeVO Seed Treatment Sudden Death Syndrome Q1: What is Sudden Death Syndrome (SDS)? A1: The causal agent of SDS is Fusarium virguliforme (or Fusarium solani f. sp. glycines). It is a soil-borne pathogen (fungus) that spreads through soil movement from geography to geography. Q2: How does SDS impact the plant? A2: Initial infections occur on the roots and crowns of young soybean plants as early as the seedling stage. This early infection causes a root rot phase that impacts the early season health of the soybean seedling. Around flowering, the fungus that causes SDS produces toxins that cause foliar symptoms including leaf drop (which reduces the plant s ability to provide nutrients to promote pod fill), aborted pods and, ultimately, yield loss. The production of the toxins and severity of symptoms is dependent on climatic conditions as well as the level of SDS genetic resistance of the seed variety used. Q3: What are the symptoms of SDS? A3: Sudden Death Syndrome symptoms include: The roots will have a blue coloration, which is indicative of Fusarium virguliforme, 1 and appear rotted. 2 The plants can be pulled easily from the soil. The internal tissue of the stem is white. 1 The areas between the leaf veins turn bright yellow then eventually brown. This brown tissue may fall out, leaving large holes in the leaves. 2 The leaf blades will fall. Q4: What is the economic impact of SDS in the United States? A4: From 2008 to 2013, average losses in the United States were estimated at 35 million bushels a year. 3 This continues to be an upward trend as the disease spreads and intensifies. Q5: What kinds of yield losses can be expected from SDS? A5: Sudden Death Syndrome is now among the top four yield-robbing diseases in soybeans. Yield losses that are commonly reported are 20 to 30 percent of a crop, but cases have occurred where yields were reduced by greater than 70 percent due to SDS. - 1 -
Q6: What conditions favor development of SDS? A6: Sudden Death Syndrome appears to develop in cool, wet weather and with soil compaction. Temperatures below 60 F at planting are ideal for infection, but greenhouse research has shown that infection can still occur at temperatures up to 82 F during planting. Moderate temperatures (about 80 F) during the growing season lead to SDS symptoms developing on the leaves. 2 Moisture enables the SDS pathogen to penetrate the soybean plant via the root system. 1 Soil compaction studies at Southern Illinois University prove that higher compaction leads to higher levels of SDS. If the root is constricted, there is more stress on the plant and there is more moisture for longer periods. 1 Q7: What can growers do to prevent SDS from occurring? A7: Growers should use an integrated approach to manage and prevent SDS. Though there are no seed varieties with absolute resistance, resistant soybean varieties are available as a first line of defense. Growers should select soybean varieties with the greatest resistance to SDS to plant in the fields with a history of SDS problems, as well as take measures to avoid or reduce soil compaction. In addition, growers should consider improving soil drainage, if possible, in fields with recurring SDS problems. 2 Q8: Are there any treatment options available on the market to prevent or control SDS? A8: Until now, there were no seed varieties with absolute resistance to SDS or effective chemical treatment options on the market. Recently approved by the EPA, ILeVO from Bayer CropScience provides breakthrough protection for soybean seedlings from SDS. In Bayer SeedGrowth research and field trials, ILeVO seed treatment has shown excellent activity against early-season infection in soybeans which reduces the incidence and severity of the impact SDS has later in the season. Q9: Can SDS be confused with other diseases affecting soybeans? A9: Sudden Death Syndrome symptoms can mimic symptoms of a disease called Brown Stem Rot (BSR). The distinguishing feature between a soybean with SDS and BSR can be found in the center of the stem. With BSR, the center of the stem will be brown. With SDS, the center of the stem will appear white. Additionally, the roots of soybeans with SDS will have a blue coloration, which is indicative of Fusarium virguliforme, the fungus that causes SDS. 1 Q10: Can SDS affect other row crops, such as corn? A10: Sudden Death Syndrome only affects soybeans; however, the fungus that causes SDS can survive and overwinter on corn or cotton residue, making soybean to corn or cotton crop rotation a less than ideal management practice. Q11: Where was SDS first identified in North America? A11: First discovered in Arkansas in 1971, SDS has been documented in almost every state in which soybeans are grown. The states that currently report the most cases of SDS are Ohio, Illinois, Indiana and Iowa. Growers in Canadian soybean areas have also reported cases of SDS. - 2 -
Q12: Does SDS reduce grain quality or cause problems after harvest? A12: No, SDS does not infect the grain directly, but the disease causes flower and pod abortion, leading to lower yields. Plants severely affected with SDS produce smaller than normal seed. Q13: Can there be a co-infection with SDS and Soybean Cyst Nematode (SCN) if both exist in the same field? A13: The combination of the Fusarium virguliforme fungus (which causes SDS) and SCN in a field will have a greater impact on the potential yield of a seed variety that is susceptible to both pathogens than either pathogen would individually. A plant may be infected with both pests. 1 North Central Soybean Research, SDS Update. 2 A. Robertson, L. Leandro, Department of Pathology, Iowa State University. 3 A. Wrather, University of Missouri, United Soybean Board-funded project. Nematodes Q1: Do nematodes have a significant impact on soybeans? A1: There are three main nematode types that can impact soybeans: Root-Knot Nematode (RKN), Soybean Cyst Nematode (SCN) and reniform nematode. Reniform and RKN are mainly problems in the southern U.S. and cause significant economic loss. The number one pest in soybeans every year is SCN, which over the past five years has caused an average loss of 126 million bushels per year. 1 Even with resistant seed sources, SCN causes significant yield losses. Nematode symptoms are not unique or diagnostic, and it is important to know yield loss is occurring without above-ground symptoms. Q2: Is there a correlation to yield impact between SDS and SCN? A2: There are well-known interactions between nematodes and certain seedling pathogens. One interaction related to soybeans that is often mentioned is that of SDS and SCN. If both pests, SDS and SCN, are present in a field, the impact on yield can be more severe than if only one is present. In either scenario, whether both pests are present or only one, ILeVO can help improve yield potential by protecting the root against nematode activity and the SDS fungus in the early stages of development. However, other seedling diseases require a good base seed-applied fungicide regimen to keep problems minimized. 1 A. Wrather University of Missouri, United Soybean Board-funded project. ILeVO Seed Treatment Q1: What is ILeVO? A1: Recently approved by the U.S. EPA, ILeVO, developed by Bayer SeedGrowth is a revolutionary seed-applied fungicide that provides breakthrough protection for soybean seedlings from SDS. Until now, there were no seed varieties with absolute resistance to SDS or effective chemical treatment options on the market. - 3 -
Q2: How does ILeVO seed treatment work? A2: The active ingredient in ILeVO is absorbed by the germinating seed and moves systemically into the seedling s roots, cotyledons and developing leaves (unifoliates). This unique mode of action provides early protection against SDS. Q3: For which crop will ILeVO be labeled? A3: ILeVO seed treatment is registered for use on soybeans to provide early-season control of SDS, a soybean-specific disease, as well as control of plant pathogenic nematodes in the soil area surrounding the seed and seedling roots (seed zone). Q4: When will ILeVO be available for use in the United States? A4: ILeVO is now available to growers in the United States for the 2015 growing season. Q5: What ILeVO research trials has Bayer completed? What are the results? A5: During research and field trials from 2011 to 2014, ILeVO was used on 190 fields with visual symptoms of SDS. Yield benefits have ranged from 2 to 10 bu./a depending on nematode pressure and SDS incidence or severity. Q6: What are some of the benefits beyond the control of SDS that a grower can expect to see when using ILeVO? A6: In addition to managing the impact of SDS on the plant, ILeVO provides activity against nematodes in the seed zone. Nematodes cause significant yield loss every year across all soybean-producing geographies. Specifically, Soybean Cyst Nematode (SCN) causes more yield loss in soybeans year after year than any other pest, and ILeVO has been shown to be effective against this pest. Q7: How does ILeVO impact nematodes? A7: ILeVO brings a new mode of action for nematode control to the market by disrupting nematode respiration through contact and ingestion activity. Q8: Which nematodes is ILeVO labeled for? A8: Currently, ILeVO is labeled for lance, reniform, root lesion, root-knot and soybean cyst nematodes. But be sure to read the label at the time of use for the most current list. Q9: Is ILeVO compatible with other seed treatment products? A9: ILeVO is compatible with all Bayer SeedGrowth seed-applied fungicides and insecticides, including Poncho /VOTiVO. Initial compatibility testing of ILeVO with Rhizobium went well, and additional testing is underway with major Rhizobium suppliers. Check suppliers websites for updates on ILeVO compatibility with Rhizobium products. Consult your Rhizobium supplier or local Bayer CropScience SeedGrowth technical service representative prior to use for guidelines on compatibility testing outside the Bayer SeedGrowth portfolio. - 4 -
Q10: Is any special equipment needed to apply ILeVO to the seed? A10: ILeVO seed treatment can be applied with the same commercial seed treatment equipment used to apply other Bayer SeedGrowth products. Downstream, ILeVO may be mixed in slurry or applied neat through a static mixer or direct injection system. An adequate slurry rate should be used to provide acceptable coverage and seed-to-seed distribution. ILeVO may also be applied using the On Demand system, a revolutionary seed treatment solution that brings commercially treated precision and downstream control to retailers and seed dealers by offering the most advanced seed treatment system on the market. It is the first and only fully automated seed treatment system developed to make treating seeds easier, more accurate and more efficient. ILeVO is not registered for use in on-farm applications. Q11: Is planting accuracy affected on ILeVO-treated soybean seed? A11: In Bayer SeedGrowth testing, there was no impact on the planting accuracy of ILeVOtreated seed versus untreated seed, even when tested under extreme conditions (e.g., high heat/humidity and with no planter box talc or graphite). Bayer SeedGrowth supports planter manufacturer recommendations on the use of planting lubricants, including Bayer Fluency Agent, to optimize performance during planting. Q12: Does ILeVO seed treatment have any known impact on the environment? A12: ILeVO is applied to the seed, which reduces direct exposure to the environment compared to other crop protection methods of application. Bayer CropScience sees seed treatment technology as an essential part of sustainable agriculture. The amount of product used is far less than foliar applications since broadcast foliar applications are applied to 100 percent of a field, while less than one percent is treated using seed treatments. The Halo Effect Q1: How will growers know that ILeVO is working? A1: Growers may see a Halo Effect on the cotyledons a visual confirmation that ILeVO is circulating through the plant enabling protection from SDS. The Halo Effect appears on the edge of the cotyledons as a discoloration ranging from light green to yellow to brown. The cotyledons contain the stored food reserves of the seed. As these reserves are consumed, the cotyledons wither and fall off. Nutrients are then supplied through the unifoliates and the trifoliates (true leaves) of the seedling. Since SDS symptoms are rarely seen in seedlings, the Halo Effect provides growers with confidence that ILeVO is defending the plant. Q2: What causes the Halo Effect on the cotyledons? A2: The Halo Effect is limited to the cotyledons and does not appear on the unifoliates or trifoliates. The discoloration is limited to the edge of the cotyledons and is triggered by the ILeVO seed treatment that is absorbed into the cotyledons after systemic movement. - 5 -
Q3: How long does the discoloration last? A3: The discoloration lasts until the cotyledons fall off. Once plant growth results in unifoliates and initial trifoliate production, the plant will appear normal in color. Q4: Is there a growth response to ILeVO? A4: In some instances, growers may initially see a slower growth response as the soybean plant begins to process or metabolize ILeVO. The slower growth allows the developing plant time to build up its internal resistance to SDS, effectively jump-starting the plant s defense response in a manner similar to the way the human body reacts to vaccines. Twenty to 30 days after emergence, growers will begin to see a healthier looking plant, compared to untreated soybeans, because of the effective control of SDS. Q5: Is there an effect on seedling emergence or plant stands with ILeVO? A5: After three years of field testing, soybeans treated with ILeVO emerge at the same speed as untreated beans. The presence of ILeVO does not impact emergence or plant stands. Q6: Does ILeVO trigger a response to herbicides? A6: Bayer CropScience research in 2013 and 2014 showed no interaction with pre-emergence herbicides. Both Bayer CropScience and university researchers performed field and greenhouse trials to identify any potential herbicide interactions. Q7: Where can growers go to learn more about ILeVO, the Halo Effect and Sudden Death Syndrome (SDS)? A7: For more information on ILeVO, the Halo Effect and Sudden Death Syndrome (SDS), please contact your local Bayer representative or visit www.bayercropscience.us. 2015 Bayer CropScience LP, 2 TW Alexander Drive, Research Triangle Park, NC 27709. Always read and follow label instructions. Bayer (reg d), the Bayer Cross (reg d), ILeVO, Poncho, VOTiVO, SeedGrowth, and On Demand are trademarks of Bayer. ILeVO is now available for sale. This Q+A is provided for informational purposes only and is not intended to promote the sale of these products. Any sale of these products shall be solely on the basis of the EPA-approved product label(s), and any claims regarding product safety and efficacy shall be addressed solely by the label(s). For additional product information, call toll-free 1-866-99-BAYER (1-866-992-2937) or visit our website at www.bayercropscience.us. CR0115ILEVOOA041V01R0-6 -