Plant & Soil Sciences Extension Newsletter

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1 Plant & Soil Sciences Extension Newsletter 368 Ag Hall Stillwater, OK May 16, 2008 Volume 1 Issue 10 PVP Protection and Jagger I N THIS ISSUE PVP and Jagger Double-crop soybean New faces in PaSS Many Oklahoma wheat farmers might be a bit surprised to learn that Jagger is a PVPprotected variety. To my knowledge, however, Kansas State University has never enforced the PVP protection on Jagger. This is about to change. Kansas State recently transferred ownership of the varieties Jagger, Overley, Fuller, RonL, and Danby to the Kansas State University Research Foundation who subsequently licensed them to the Kansas Wheat Alliance (KWA). In a recent news release KWA indicated their intent to fully enforce PVP protection on these varieties in the fall of They will use the Farmer s Yield Initiative and similar investigative services to accomplish this task. A copy of the press release is attached at the end of this article. So, what does this mean for Oklahoma producers? If you are simply saving seed to plant on your own farm, there is really no impact. If you had planned to sell brown bag seed to neighbors, though, you will likely want to reconsider. More information can be found at the Kansas Crop Improvement website at or at the Farmer s Yield Initiative website at Jeff Edwards jeff.edwards@okstate.edu Plant and Soil Sciences, OSU Press Release from KWA Wheat Alliance to explain new license agreement Beginning in the fall of 2008, anyone producing the wheat varieties Jagger, Overley, Fuller, RonL, and Danby for sale as seed will need to complete a license agreement with the Kansas Wheat Alliance (KWA). This change in the variety marketing system will also include a royalty on each sale, beginning in Kansas State University Research and Extension has signed a material transfer agreement with Kansas State University Research Foundation for these varieties, and an agreement was subsequently signed with KWA to develop a marketing plan for them. Three opportunities are available for wheat

2 Page 2 Jagger continued from page 1 farmers and seed producers to learn about KWA s marketing plan for the five K State wheat varieties affected by this agreement. The first opportunity to learn about this new system is May 20 at the South Central Kansas Experiment Field near Hutchinson. The Spring Field Day begins at 8 a.m. with a Wheat Variety and Disease Update from KSU wheat breeder Allan Fritz and plant pathologist Erick DeWolf. Several crop management presentations will follow. At approximately 10 a.m. there will be a presentation about the Kansas Wheat Alliance and explanation of the variety license agreement. On May 21, Wheat Day will be held at the KSU Hays Research Center. A presentation will be made at 1 p.m., followed by the variety plot tour with wheat breeder Joe Martin at 3:30. Following the plot tour will be a presentation about the Kansas Wheat Alliance and the license agreement. The third presentation is scheduled for 1:30 p.m. on May 22 at the KSU Agronomy Farm, Ashland Research Unit, south of Manhattan. Allan Fritz will give a tour of the wheat nursery and discuss the focus of his breeding program, followed by a presentation about KWA and the license agreement. Daryl Strouts, executive director, will be making the presentations for KWA and explaining the license agreement. For additional information, contact the KWA office at or e mail kwa@kansas.net. Double-crop Soybean Production in Oklahoma Double cropping soybeans after winter wheat should be popular (market price) and feasible (soil moisture availability) in much of the eastern two thirds of Oklahoma this year. This cropping system has several advantages: 1) spreads annual fixed costs such as land, taxes and machinery over two crops instead of one providing the potential for increased gross returns per acre with relatively low increases in production costs (greater profit potential) and 2) a crop growing on the land all year reduces soil erosion. A successful wheat double crop soybean system depends on management and weather conditions. Establishing an adequate soybean stand is critical. In order to accomplish an adequate stand it first starts at wheat harvest. Residue Management Wheat straw can act as a mulch to conserve soil moisture, impede runoff and prevent surface crusting. No till practices are valuable in situations where moisture for germination is limited, as is normally the case after wheat harvest. However, residues can make planting difficult. These problems can be overcome with proper equipment and straw management. In a no till system, small grain residue should not be bunched or windrowed unless it is to be baled and removed. Planters cannot penetrate such residue and still place seed at the proper depth. A simple way to manage wheat straw in a no till system is to cut the wheat at normal height, shred the straw with a shredder attachment on the combine, and distribute it evenly across the length of the wheat platform.

3 Page 3 Shade provided by standing stubble stimulates elongation of soybean stems and causes a higher first pod height. This makes soybean harvest easier and reduces harvest losses. If the stubble is too high, plants will be spindly and susceptible to lodging. Variety Selection In the case of double crop soybean production in northern Oklahoma a MG IV or V will perform the best planted in June and early July. The southern parts of the state can plant MG IV to VI. When selecting a variety for high yield, consider performance results from several locations and years. Seeding Rate The recommended plant population for most of Oklahoma is to have ~100,000 plants per acre at harvest time. However, selecting a proper soybean seeding rate should take into account variety, row width, and production region. High soybean yields are possible with a wide range of plant populations because single plants of most varieties will utilize a 7 to 9 inch area in all directions around the main stem. A soybean plant has a tremendous ability to compensate for variations in population. Therefore, the penalty for over planting or under planting may be relatively small. Plants adjust to low populations by producing more branches per plant and by increasing the number of pods on both the main stem and branches. There is, however, little change in seed size and in seed number per pod. When grown under high populations, individual plants produce fewer pods, fewer branches, grow taller, and pod higher off the soil surface than when grown at low populations. Yield potential is maintained with high populations since there are more plants per acre. Seeding rate should be based on seeds per foot of row and not on pounds per acre. Table 1 provides the number of seeds per foot of row required to achieve a certain final plant population. Three levels of germination are used as examples. Most purchased seed is tagged at 80% germination, which is the lowest germination acceptable by certification standards. The seed may actually have a higher germination resulting in a thicker stand. Table 1. Suggested plant populations and seeding rates for soybean planted in Oklahoma. Seed per foot of row* Row width Feet of row per acre Plants per foot of row Plant Population per acre 90%** 80% 70% 40 13, , , , , , , , , , , , , , , , , , *Assuming 90% field emergence of the live seed. **Germination percentage indicated on the bag.

4 Page 4 Even though the germination of your planted variety may indicate 80%, is very unlikely that the final plant stand will be 80% of planted seed. The seeding rates in Table 1 assume 90% emergence of the planted seed. To calculate the rate of seed per foot of row, use the following formula: Some special circumstances may result in increasing the seeding rate. These are only suggestions and do not replace personnel experience. Increase the seeding rate for the following situations: 10% for rough seedbed 10 20% for no till 15% for planting after July 1 Row width As row width is narrowed, planting rate per foot of row should be reduced. Use of lower or higher plant population within certain row spacing should depend on the fertility level of the field, lodging resistance of the variety, and the architecture of the variety to be planted. Varieties susceptible to lodging or having a strong tendency to branch may perform better at lower populations. Also, the penalty for overplanting or under planting non branching varieties may be more severe than those that tend to branch profusely at low populations. The branching variety will be able to compensate for a thin stand. Table 1 indicates a general increase in plant population as you decrease row spacing. This can be done because plant to plant spacing is still similar even though you increase population. The plant still has that 7 to 9 inches or area to utilize. Research in Oklahoma has not shown consistent yield response with row spacing of 30 or less. In the eastern US, a consistent response has been observed with narrow rows. In theory, the advantage of narrow rows over wide rows will be greater when early maturing varieties are planted very early or when the planting date for medium maturing varieties is delayed beyond June 15. In the case of double crop soybean, if planting is delayed after June 15, it would be recommended to reduce row width to less than 30. Planting Depth and Date Soybean seed should be planted 1 to 1 ½ inches deep. This varies with the type of soil and existing moisture conditions. Soybean should be planted shallower in clay loams and other fine textured soils compared to sandy soils. A 2 planting depth is the maximum on sandy soils. Planting should occur as soon as wheat harvest is complete as possible. Planting can occur until July 10 but a slight to moderate reduction in yield can be expected by planting in early July. Planting date is important to maintain high yield potential. Fertility Fertilizing for the soybean crop at the same time you fertilize for your wheat crop is more practical than trying to make an additional application after wheat harvest. Time will be saved at a critical period. The higher fertility level may also benefit the wheat. If the soybean double crop cannot be planted, the extra phosphorus and potassium applied will remain in the soil to benefit subsequent crops. Determine the soil fertility status with a reliable soil test and base expected crop yield on past experience. Soil ph should be in the 5.8 or greater. Yield loss can be expected if soil ph is below 5.8

5 Page 5 Inoculant is critical to the success of the soybean crop. Nitrogen is typically not a concern with soybean production, since they are legumes and manufacture an adequate amount of nitrogen for their own needs. The plant supplies the bacteria with an environment and nutrients in which to survive and multiply. In turn, the bacteria convert atmospheric nitrogen into a form that can be used by the plant through a process called nitrogen fixation. In order for nitrogen fixation to occur Rhizobium bacteria must be present in the soil. Sometimes soils contain and adequate amount of Rhizobium bacteria, however, it is a risk not worth taking. In most cases, application of an inoculant calculates to <2 percent of your production costs so it is a wise investment. With proper seed inoculation using soybean specific inoculants, you increase your chances of having good nodulation. Inoculants can be applied to the seed (liquid), in a hopper box mixture (powder) or directly into the ground (granular) with an in furrow application. Liquid inoculants are currently the most popular. Powder inoculants should not be used if other sources of inoculant are available. Powder inoculants may not perform as well when compared with liquid and granular types, especially if an additive is not used to adhere the inoculum to the seed. Producers should consider the following when making inoculant choices: 1. The cost of inoculant per number of Rhizobium bacteria. 2. Consider how it will be applied and whether any preparation of the product is needed. 3. Compatibility with seed, fertilizer, and other chemical treatments. As a general rule of thumb, insecticides are more toxic than fungicides, which are more toxic than herbicides. Extreme importance should be used when handling and storing inoculants as it is a live bacteria! Inoculants should be stored in a cool (<90 o F), dry area and never exposed to sunlight. As with any other product, always read and follow label directions. Four to six weeks after planting, plants may be dug up and evaluated for nodulation.

6 Page 6 Learn About the Newest PaSS Extension Team Members Precision Nutrient Management: putting fertilizer only where it is needed. Many of you know who I am; however, I recently changed roles. For the past few years, I worked along side Dr. Bill Raun as the Soil Fertility Senior Agriculturalist. Recently, after completing my Doctorial studies, I transitioned into the position of Precision Nutrient Management Extension Specialist. My appointment is 70/30 Extension and Teaching. I look forward to spending much of my time interacting with all OSU Extension personnel. I will continue extending the products of the Soil Fertility Research Project (N Rich Strip, Ramp Calibration Strip, and Green Seeker Sensor). I will also be exploring different methods of extending technology to reach new audiences and increase adoption. Two major projects I will be pursuing in the realm of Precision Nutrient Management are the use of sensors for mid season side dress N application in cotton and the comparison of N management strategies on a much larger scale. For the latter, I will need the help and cooperation of Area Agronomists and County Educators. I am eager to work with everyone to increase the awareness of Precision Nutrient Management to producers in Oklahoma and across the nation. I am at your service for any questions related to nutrient management, and will regularly update and release new fact sheets and extension material. Brian Arnall b.arnall@okstate.edu Plant and Soil Sciences, OSU Plant Science Teaching and Extension/Youth Development I m very excited to be one of the most recent additions to the Department of Plant and Soil Sciences at OSU! My responsibilities are primarily in undergraduate teaching, which means I have to opportunity to help the students in our department develop the knowledge and skills they ll need to be outstanding representatives of themselves and their University following graduation. My extension responsibilities are primarily related to youth development. I m looking forward to working with extension personnel across the state to develop programs that will increase students understanding and appreciation of agriculture, especially the plant sciences. My goal is to help all of the students I work with develop skills that will enable them to contribute to Oklahoma s agricultural industry. I m also looking forward to working with extension specialists to provide information related to crop production for the purpose of enhancing the knowledge of Oklahoma producers. Please contact me if you have any questions, comments, or concerns. Sarah Lancaster sarah.lancaster@okstate.edu Plant and Soil Sciences, OSU Plant ant Soil Science Extension Oklahoma State University 368 Ag Hall Stillwater, OK Phone: Subscription information The is published in electronic format on an as needed basis throughout the year. To receive an electronic copy in pdf format, go to and follow the instructions.