NC1195: Enhancing nitrogen utilization in corn based cropping systems to increase yield, improve profitability and minimize environmental impacts

(Multistate Research Project)

Status: Active

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Annual/Termination Reports:

[03/21/2022] [05/12/2023] [05/07/2024]

Date of Annual Report: 03/21/2022

Report Information

Annual Meeting Dates: 03/01/2022 - 03/02/2022
Period the Report Covers: 03/04/2021 - 02/28/2022

Participants

Participants Attachment:

NC 1195 Meeting Minutes 2022.docx

Brief Summary of Minutes

Minutes Attachment:

NC 1195 Meeting Minutes 2022.docx

Accomplishments

<ol> <li>Determine the roles of innovative management practices, the environment, and their interactions on optimum use of nitrogen in agroecosystems.</li> </ol>   Short-term Outcomes:   Across multiple locations, Jagadamma and Poffenbarger found that legume and mixture cover crops did not have a significant impact on the optimum N rate of corn. However, Norton found that hairy vetch contained about 110 kg N/ha in aboveground biomass, and estimated that it would provide about 55 kg N/ha to the subsequent corn crop. In a multi-state coordinated study, Poffenbarger found that cereal rye significantly increased the optimum N rate of corn by over 50 kg N/ha. In a laboratory study, Saha found that increasing drying-rewetting intensity of the soil increased N2O emissions and that the presence of cover crop residue reduced the N2O emissions under extreme drying-rewetting.     In field research studies evaluating different nitrogen fertilizer sources, Yin found that non-stabilized dry urea and broadcast UAN produced high ammonia volatilization. Adding ANVOL, a urease inhibitor, reduced ammonia volatilization with all surface-applied urea and UAN treatments. In addition, ANVOL increased corn grain protein numerically and grain yield +4 to +13 bu/Ac when added to UAN in the row middle (dribble), UAN Y-drop, UAN broadcast, or urea broadcast N. Urea + ANVOL yielded statistically similar in corn as potentially higher cost specialty urea products such as ESN and SuperU.   Arnall has been summarizing 20 years of approximately 100 site-years of winter wheat N rate and timing work in Oklahoma, finding that the optimum timing of N application for wheat was at the Feekes 6 stage. While developing N uptake curves for low and high protein varieties, he determined that low protein wheat accumulates a larger proportion of N by anthesis than high protein wheat.   Horwath found that microirrigation systems (surface or subsurface drip) substantially decrease N2O emissions from the soil as compared to flood irrigation systems.   Outputs:   Over the past year, our group has produced three peer-reviewed publications and five presentations about how cover crops affect soil N cycling. The group has also presented about enhanced efficiency nitrogen fertilizers and their impact on ammonia volatilization loss (one presentation). In addition, several graduate students and undergraduate students have been trained in these projects, and more outreach is planned to share these results. Norton is planning to use data collected on the N contribution of vetch cover crops to corn to make adjustments for N recommendations in Utah. Activities:   In 15 states across the U.S., researchers are conducting a coordinated study to determine how legume, cereal rye, and rye-legume mixtures affect the optimum N rate for corn as compared to no cover. This study will continue for two more years.   In Tennessee, Jagadamma has been studying how cover crops (wheat, crimson clover, wheat-clover mixture, a five-species mixture of wheat, oats, crimson clover, hairy vetch, and daikon radish) affect N fertilizer needs of the subsequent corn crop as compared to no cover.  Through periodic soil and plant sampling, and the use of resin membranes in-situ, the project will determine if producers can reduce N application to corn by growing winter cover crops and if so, which cover crop species is most suitable for providing N credits to corn.   In Tennessee, Saha has been studying how cover crops affect soil N2O emissions, particularly under increased rainfall variability caused by climate change. A laboratory incubation was conducted to examine cover crop roles in N2O emissions from N fertilized soils when exposed to different rewetting-drying intensities. These factors included i) cover crop residue (3 levels): no cover crop, winter wheat, and crimson clover, ii) rewetting intensity (2 levels): 70 and 90% water-filled pore space (WFPS), and iii) drying intensity (2 levels): 10 and 40% WFPS. Urea fertilizer with or without dry cover crop residues were mixed in repacked soil cores. The group measured N2O, CO2 fluxes, and N2O isotopomer composition and soil biogeochemical variables. Saha is also leading an effort to quantify tillage, cover crop, and nitrogen fertilization effects on O2 and N2O fluxes in the field, and to develop a machine learning modeling approach for N2O prediction using soil O2 and other biogeochemical variables as predictors.   Also in Tennessee, Yin has been studying how different fertilizer sources, methods of application, and enhanced efficiency products affect ammonia volatilization and corn yields.   In Oklahoma, Arnall is completing the final analysis and summation of three years of a large scale corn nitrogen rate by water rate study. A focus of this project is the evaluation of spatial and temporal variance. A thesis and peer review publication will be completed in 2022. In addition, Arnall is developing nutrient uptake curves of known low protein and high protein wheat cultivars and implementing a winter wheat study that will evaluate the potential for a relationship between genetic background and optimum nitrogen fertilizer timing.   <ol start="2"> <li>Understand the role of soil biological processes in controlling plant available nitrogen and their relationships with soil health and system resilience.</li> </ol>   Short-term Outcomes:   McDaniel, in collaboration with Drijber and their students, staff and faculty colleagues have been studying soil biological properties in the rhizosphere and bulk soil of corn fields. The team has found that diversified crop rotations dampen the rhizosphere effect and decrease the effect of corn roots on soil microbes and carbon in particular as compared to short crop rotations. The lower allocation of carbon to roots in the long rotation may help to explain why corn performs better in the long rotation.   Laboski found that measurements of POX-C and ammonium collected at planting were good predictors of the economic optimum N rate of corn and performed better than the current recommendation system, the maximum return to N. Horwath found that composts and cover crops did not lead to significant carbon sequestration in California, or improvements in crop yield.   Outputs:   The group has produced four peer-reviewed publications and two presentations about the effects of management on soil health and soil biological processes.   Activities:   Drijber Initiated and sampled soil from three collaborative field experiments this past year for assessment of soil microbial community impacts (particularly on arbuscular mycorrhizal fungi) from a variety of crop and soil management practices:   <ol> <li>In collaboration with Brian Arnall from Oklahoma State University (NC1195 committee member) we sampled his ongoing field trails for winter wheat and sorghum to evaluate the impact of delayed N fertilization on the soil biomass and seasonal dynamics of arbuscular mycorrhizal fungi, an important contributor to plant nutrient uptake and soil C sequestration.</li> <li>The second study revisited UNL’s Roger’s Memorial Farm four years after conversion of all tillage plots to no-till and introduction of cover crops to evaluate recovery of no-till soil microbial communities and soil health parameters.</li> <li>In collaboration with the USDA-ARS group in Lincoln, NE, we also had the opportunity this spring to soil sample Galen Erickson’s long-term cattle grazing trial comparing fertilized, supplemented and control paddocks for soil health measures, N-cycling genes and soil microbial communities.</li> <li>Continued our research into biochar impacts on soil microbial communities and soil health parameters.</li> </ol>   McDaniel and Drijber, along with graduate students and other faculty colleagues are studying corn rhizosphere dynamics in long and short crop rotations to explore whether differences in rhizosphere dynamics could explain better corn yield in long rotations.   Norton and her undergraduate students sampled vetch shoots and roots with nodules before termination and investigated nitrogen fixing bacteria from these samples. Several nodule occupants were isolated and chosen for draft genome sequencing. All were closely related to Rhizobium leguminosarum. Refinement of sequences and further characterization of biological N fixation by vetch cover crops continues.   McDaniel and Laboski have been compiling data from members of the NC1195 committee to understand the relationship between soil health indicators and the economic optimum N rate of corn.     <ol start="3"> <li>Translate field and laboratory research into nitrogen management decision-making tools and educational resources promoting improved profitability and sustainability of corn-based cropping systems.</li> </ol>   Short-term Outcomes: To engage students, the general public, growers, and crop advisers in learning about nitrogen cycling in Iowa agricultural systems and nitrogen reduction strategies, we used teaching and learning materials that were created in 2019-2020. This included a user-friendly, process-based simulation model of nitrogen cycling in agricultural systems and the accompanying instructional materials. The learning materials were used in undergraduate ecology courses, 45 students at ISU and 50 at Lake Superior State University. Since its inception in 2020, the website has had ~600 page views and 150 downloads.   Yin determined that the reference N sufficiency range for corn at the seedling stage is too low for current cultivars, while the ranges at tasseling and maturity are too high. These will need to be modified with further research.   Outputs:   Instructional materials about nitrogen cycling in agricultural systems were hosted on this website, <a href="https://nmodel.nrem.iastate.edu/">https://nmodel.nrem.iastate.edu/</a>, and published.   The group has produced three extension or outreach presentations in the last year, and also one newsletter article for producers about cover crop effects on optimum N fertilization practices.   Activities:   In Iowa, Russell has been developing learning modules and case studies for students and producers using an open-access platform called Gala. The platform allows others to provide comments before finalizing the modules.   Li used Monte Carlo simulations and on-farm experiments to evaluate the economic performances of different trial designs in site-specific nitrogen rate recommendations, and identified the most profitable trial design selection for on-farm nitrogen experiments.   Khanal is using remote sensing to understand cover crop presence, biomass, and impact on cash crop yield across large areas of Western Lake Erie Basin.   Several group members including Li, Khanal, Saha, and Poffenbarger are using or interested in using machine learning tools to translate large datasets into predictive tools that could be used to inform farmer decision-making.

Publications

Impact Statements

- Results of this research will make cover crop integration more successful in corn-based cropping systems and avoid excess N fertilizer application when cover crops are implemented. - The emerging relationships between soil health indicators and the economic optimum N rate will help to advance soil testing to improve the precision of N fertilizer management. - Understanding how management practices such as irrigation method and cover crop use affect N2O emissions will inform strategies to reduce the carbon footprint of agriculture. - Online nitrogen cycling educational materials enable current and future agricultural practitioners to make more informed N management decisions. - Peer-reviewed articles, 24 published since our last NC1195 meeting, disseminated research findings to the scientific community. - Presentations at conferences and meetings, 33 since our last NC1195 meeting, disseminated research results to professional societies, commodity groups, and stakeholders. - Funding from 28 grants obtained by participants on this project in 2021 or ongoing enable this research to continue.

Date of Annual Report: 05/12/2023

Report Information

Annual Meeting Dates: 03/07/2023 - 03/08/2023
Period the Report Covers: 03/01/2022 - 03/06/2023

Participants

Canisares, Lucas (Lucas.canisares@uky.edu) – University of Kentucky; Erickson, John (john.erickson@usda.gov) – NIFA National Program Leader; Horwath, William wrhorwath@ucdavis.edu) – University of California Davis; Khanal, Sami (khanal.3@osu.edu) – Ohio State University; Laboski, Carrie (laboski@wisc.edu) – University of Wisconsin; Lamkey, Kendall (krlamkey@iastate.edu) – Iowa State University; Li, Xiaofei (xiaofei.li@msstate.edu) – Mississippi State University; McDaniel, Marshall (marsh@iastate.edu) – Iowa State University; Norton, Jeanette (Jeanette.norton@usu.edu) – Utah State University; Owens, Vance (Vance.Owens@usda.gov) – USDA-NIFA National Program Leader; Poffenbarger, Hanna (hanna.poffenbarger@uky.edu)- University of Kentucky; Russell, Ann (arussell@iastate.edu) – Iowa State University; Saha, Deb (dsaha3@utk.edu) – University of Tennessee; Yin, Frank (xyin2@utk.edu) – University of Tennessee

Brief Summary of Minutes

Welcome, introductions, agenda review: the meeting started with a general welcome to the group and reviewing the agenda. Introductions were done with the whole group. About 40% of the 16 committee members virtually attended the meeting.

State report highlights: All attendees gave 20-35 minutes presentations about their work relevant to this project theme, followed by a discussion of each topic area.
- Will Horwath (University of California Davis): Compost effects on C and N cycling dynamics in California Tomato cropping systems
- Matthew Ruark (University of Wisconsin-Madison): Cover crop biomass and soil nitrate by rye seeding rate; nitrogen fertilizer rate on corn yields; shoot: root biomass of rye biomass by rye seeding rate
- Marshall McDaniel (Iowa State University): Are labile C and N like Las Vegas – What happens in the surface stays in the surface?
- Peter Tomilson (Kansas State University): Legacy effects of cover crops on N availability in the cropping system and yield response to N fertilization; Flickner Innovation Farm: Paired watershed
- Daniel J. Quinn (Purdue University): N fertilizer Research; Impact of in-season N fertilizer timing in cover crop systems
- Sami Khanal (Ohio State University): Simulated effects of management practices on greenhouse gas emissions and soil organic carbon in the Maumee River Watershed
- Debasish Saha (University of Tennessee): Nitrous oxide emissions from long-term soil health practices
- Xiaofei Li (Mississippi State University): Economic performance of MRTN using on-farm precision experimentation data
- Rhae Drijber (University of Nebraska-Lincoln): Harnessing soil biology for improved crop production
- Ali M. Nafchi (South Dakota State University): Using next-generation of precision ag applications to enhance nitrogen use efficiency
- Mike Castellano (Iowa State University): Initiative to expand MRTN recommendation to account for genetic, environmental, and management factors that affect the dynamic nature of optimal N rates.
- Brian Arnall (Oklahoma State University): Precision nutrient management in corn-cotton rotation production system
- Fabian Fernandez (University of Minnesota): Mitigating nitrate, nitrous oxide, and ammonia loss in corn with a nitrogen source and application timing
- Hanna Poffenbarger (University of Kentucky): How do cereal rye and legume cover crops affect corn's optimum N fertilizer rate?

Administrative Update: John Erickson provided an administrative update on NIFA staffing/hiring status, as well as changes & reorganization to the AFRI program priority areas.

Meeting in 2024: The group agreed to hold the next meeting on February 28-29, 2024, at Fairfield Inn and Suites, Kansas City, MO.

Executive committee changes: The current Secretary, Sami Khanal, will be the Chair in 2024; the current Member-at-Large, Debasish Saha will be the Secretary. Peter Tomlinson was elected as the Member-at-Large for 2024. The current Chair, Hanna Poffenbarger, will be the past Chair.

Accomplishments

Impact Nugget: A concise statement of MULTISTATE advancements, accomplishments, and impacts.  <ul> <li>Advancements</li> </ul> This research project has resulted in an improved understanding of how various management practices influence nutrient and crop health dynamics, providing valuable guidance to farmers. Several works from the individual state members are in progress to develop more operation-specific recommendations, guidelines, and tools for nitrogen management. <ul> <li>Accomplishments</li> </ul> Through numerous research trials conducted across various states by NC1195 members, this research project has demonstrated the role of various nitrogen management practices, such as in-season nitrogen (N) fertilizer management, cover crops, polymer-coated urea (PCU), compost, and long-term soil health practices, on lowering carbon and nitrogen footprint of agriculture while improving crop yields. <ul> <li>Impacts</li> </ul> The NC1195 multistate group is developing guidelines and recommendations as to when farmers and consultants can use alternative N management practices (e.g., pre-plant PCU, cover crops, composts, and manure) to enhance N use efficiency (NUE), which are key to developing sustainable and regenerative agriculture in the U.S. New Facilities and Equipment. Include production areas, sensors, instruments, and control systems purchased/installed, especially if these facilities and equipment are shared between states or facilitate multistate research. <ul> <li>Poffenbarger, Ruark, Woodley, and Tomlinson are using the same NDVI-based vegetation sensor in a coordinated project to establish sensing methods to predict cover crop biomass.</li> <li>McDaniel and colleagues have started measuring soil nitrous oxide emissions via surveys using LI-7820 (LiCor, Lincoln, NE).</li> </ul>  Unique Project-Related Findings.  <ul> <li>Several years of research that doing a single pre-plant application of polymer-coated urea (PCU) compared to a traditional fertilizer (urea) results in: <ul> <li>Reduction in N loss (nitrate leaching, and ammonia and nitrous oxide emissions to the atmosphere) by approximately 48%.</li> <li>An agronomic benefit with greater grain production that compensated for the additional cost of PCU over urea. Calculated with typical prices during the study ($3.50 per bushel of corn and $0.35 per pound of nitrogen as urea and $0.55 per pound of nitrogen as PCU) the PCU application resulted in a net economic return of $4 per acre higher than when using urea.</li> </ul> </li> <li>Long-term cropping systems experiment, including small grain and manure, has a greater proportion of N in less-likely-to-leach forms of N (i.e., salt-extractable organic and microbial biomass N). <ul> <li>This long-term experiment compares corn-soybean rotation with all synthetic N fertilizers (2-year) with corn-soybean-oat/alfalfa-alfalfa with >90% of N from composted cattle manure (4-year). There are 50 lbs of N per acre in microbial biomass N in the 4-year rotation compared to 2-year to 12” depth. This corresponds to less fertilizer N inputs and less nitrate leaching to groundwater (measured via suction cup lysimeters at 1.2 m deep).</li> </ul> </li> <li>Field studies used to evaluate how forage crops such as silage corn or sorghum respond to alternative sources of N in wastes such as composts in California dairy forage systems indicated that compost had significant effects on crop yield, especially when in combination with reduced synthetic fertilizer inputs. <ul> <li>Yield results are in agreement with previous studies that found increased yields following food waste compost application in grain, perennial grass, microalgae, carrot, and tomato, following green waste compost application in corn.</li> <li>Positive compost effects on yields appeared only after year 2 and show that multiple years of annual compost application may be necessary for yield benefits to justify its use.</li> </ul> </li> </ul>  Accomplishment Summaries by Major Objectives of the Project: <ol> <li>Determine the roles of innovative management practices, the environment, and their interactions on the optimum use of nitrogen in agroecosystems.</li> </ol> <ul> <li>The study involving 24 site-year field trials has shown that legume and mixture cover crops do not have a significant effect on the optimum N rate of corn, but cereal rye increases the optimum N rate of corn.</li> <li>Artificial subsurface drainage was found to increase the N use efficiency of corn, as well as the predictability of the optimum N rate of corn.</li> <li>Split application of N fertilizer was more efficient than pre-plant N application and provided advantages when corn followed a rye cover crop because of lower plant-available N supply in this system.</li> </ul> 2. Understand the role of soil biological processes in controlling plant available nitrogen and their relationships with soil health and system resilience. <ul style="list-style-type: disc;"> <li>NC 1195 committee members reviewed and synthesized literature to determine how plant breeding has affected crop residue inputs to the soil and soil organic matter, which is an important source of plant-available N in cropping systems.</li> <li>This project committee members have contributed to determining the best methods for aggregate stability and soil carbon indicators of soil health in a study involving long-term research sites in North America.</li> <li>This project committee members comprehensively estimated the effect of various N rates on 1) corn grain yield, 2) economic return, 3) nitrogen use efficiency of corn, 4) nitrate leaching load in tile-drained fields, 5) nitrous oxide emissions, and 6) ammonia volatilization.</li> <li>Field studies involving forage crops such as silage corn or sorghum to understand how these crops respond to N inputs in California dairy forage systems have shown that multiple years of compost application improves crop yield even without applying any synthetic fertilizer N inputs.</li> <li>This project committee members published 1) a peer-reviewed article on management impacts on soils, including soil biology, and the ability of soils to retain crop residues, and 2) a peer-reviewed review article relating to soil health and N sources for plants.</li> </ul>  3. Translate field and laboratory research into nitrogen management decision-making tools and educational resources promoting improved profitability and sustainability of corn-based cropping systems. <ul> <li>The NC1195 research team quantified the profitability of variable-rate application of nitrogen fertilizer in corn production using on-farm experimental data.</li> <li>This research group has worked with a detailed process-based biogeochemical model, DeNitriification-DeComposition (DNDC), to understand the role of management practices on GHG emissions, soil carbon, and crop yields.</li> <li>The committee members are actively disseminating the findings from their research activities with farmers, consultants, and the broader agricultural community.</li> </ul>

Publications

Published Written Works.    Note: Authors in bold texts indicate the NC1195 committee members <ul> <li>Poffenbarger, H., Castellano, D. Egli, A. Jaconi, and V. Moore. 2023. Contributions of Plant Breeding to Soil Carbon Storage: Retrospect and Prospects. Crop Science, in press.</li> <li>Quinn, D., Poffenbarger, F. Miguez, and C. Lee. 2023. Corn Optimum Nitrogen Fertilizer Rate and Application Timing when Following a Rye Cover Crop. Field Crops Research 291: 108794. <a href="https://doi.org/10.1016/j.fcr.2022.108794">https://doi.org/10.1016/j.fcr.2022.108794</a></li> <li>Rieke, E.L. et al., including D. McDaniel, and H. Poffenbarger. 2022. Evaluation of Aggregate Stability Methods for Soil Health. Geoderma 428: 116156. <a href="https://doi.org/10.1016/j.geoderma.2022.116156">https://doi.org/10.1016/j.geoderma.2022.116156</a></li> <li>Maas, E., S. Archontoulis, M. Helmers, J. Iqbal, C.H. Pederson, Poffenbarger, K.J. Tebockhorst, and M. Castellano. 2022. Subsurface Drainage Reduces the Amount and Interannual Variability of Optimum Nitrogen Fertilizer Input to Maize Cropping Systems in Southeast Iowa, USA. Field Crops Research 288: 108663. <a href="https://doi.org/10.1016/j.fcr.2022.108663">https://doi.org/10.1016/j.fcr.2022.108663</a></li> <li>Quinn, D., Poffenbarger, and C. Lee. 2022. Rye Cover Crop and In-Furrow Fertilizer and Fungicide Impacts on Corn Optimum Seeding Rate and Grain Yield. European Journal of Agronomy 139: 126529. <a href="https://doi.org/10.1016/j.eja.2022.126529">https://doi.org/10.1016/j.eja.2022.126529</a></li> <li>Liptzin, De, et al., including D. McDaniel, and H. Poffenbarger. 2022. An Evaluation of Carbon Indicators on Soil Health in Long-Term Agricultural Experiments. Soil Biology and Biochemistry 172: 108708. <a href="https://doi.org/10.1016/j.soilbio.2022.108708">https://doi.org/10.1016/j.soilbio.2022.108708</a></li> <li>Rieke, E.L., et al., including D. McDaniel and H. Poffenbarger. 2022. Linking Soil Microbial Community Structure to Potential Carbon Mineralization: A Continental Scale Assessment of Reduced Tillage. Soil Biology and Biochemistry 168: 108618. <a href="https://doi.org/10.1016/j.soilbio.2022.108618">https://doi.org/10.1016/j.soilbio.2022.108618</a>.</li> <li>Bagnall, D.K et al., including D. McDaniel, and H. Poffenbarger. 2022 Carbon-Sensitive Pedotransfer Functions for Plant-Available Water. Soil Science Society of America Journal 86: 612-629. <a href="https://doi.org/10.1002/saj2.20395">https://doi.org/10.1002/saj2.20395</a></li> <li>Bagnall, D.K et al., including D. McDaniel and H. Poffenbarger. 2022 Selecting Soil Hydraulic Properties as Indicators of Soil Health: Measurement Response to Management and Site Characteristics. Soil Science Society of America Journal 86: 1206-1226. <a href="https://doi.org/10.1002/saj2.20428">https://doi.org/10.1002/saj2.20428</a></li> <li>Spargo, J. T., et al., including Arnall and F.G. Fernández. 2022. A survey to evaluate the current status of land grant university and state department of agriculture soil fertility recommendations and analytical methods. Ag. Data Commons. <a href="https://doi.org/10.15482/USDA.ADC/1526506">https://doi.org/10.15482/USDA.ADC/1526506</a></li> </ul> Scientific and Outreach Oral Presentations. <ul> <li>Canisares, L.P et al., including J Tomlinson, M. D Ruark, and H. Poffenbarger. 2022. Legume cover crops can reduce the corn reliance on nitrogen fertilizer when compared to cereal rye across multi-state field experiments. ASA-CSSA-SSSA meeting, Baltimore, MD.</li> <li>Antonio-Ordoņez, R., et al., including D Ruark, M.J. Castellano, H. Poffenbarger. 2022 Yield gap as a key metric to determining N fertilizer rates in maize crop. ASA-CSSA-SSSA meeting, Baltimore, MD.</li> </ul>

Impact Statements

Translate field and laboratory research into nitrogen management decision-making tools and educational resources promoting improved profitability and sustainability of corn-based cropping systems. The works conducted by the members of this committee have resulted in 1) guidelines for farmers and consultants to apply pre-plant PCU, which will help reduce N loss as well as improve crop yields thereby enhancing agronomic benefits and overall sustainability of corn production systems; 2) guidelines on how to successfully integrate cover crops in corn-based cropping systems by avoiding excess N fertilizer application, and lowering N2O emissions, thereby reducing the carbon and N footprint of agriculture; and 3) an improved understanding of emerging relationships between soil health indicators and the economic optimum N rate, which will help to advance soil testing to improve the precision of N fertilizer management. Additionally, the findings of the projects conducted by NC1195 committee members have been disseminated not only with the scientific community through various national and international conferences and peer-reviewed journal publications but have also been extensively shared through extension programming, such as but not only limited to presentations and training to extension educators. The impact of some of these activities has also been measured through follow-up surveys. For instance, follow-up surveys related to single pre-plant application programs showed that 38% of those farmers and consultants are using or planning to use the guidelines to apply pre-plant PCU, generating an estimated annual $8.2M increase in economic return for Minnesota farmers.

Date of Annual Report: 05/07/2024

Report Information

Annual Meeting Dates: 03/12/2024 - 03/13/2024
Period the Report Covers: 03/09/2023 - 03/11/2024

Participants

Brief Summary of Minutes

Accomplishments

Accomplishments summaries by major objectives of the project: 1) Determine the roles of innovative management practices, the environment, and their interactions on the optimum use of nitrogen in agroecosystems. <ul style="list-style-type: circle;"> <li>Based on multiple site × year data, the project members evaluated the utility and challenges of EONR based N management in corn under climate variability (annual rainfall distribution). Artificial subsurface drainage improves corn productivity and profitability in wetter years as compared to undrained soils. In wetter years, split N application reduced N rate to attain similar yield as compared to pre-plant N application.</li> <li>Team members investigated corn EONR in response to cover cropping. Based on 36 site × year data across the US, legume cover crops did not significantly reduce EONR of corn, but cereal rye and rye-legume mixtures increase the optimum N rate.</li> <li>Multiple project members investigated long-term impacts of no-tillage and cover cropping on soil health indicators, N2O emissions, and profile soil C. Cover crops positively influenced soil biological health indicators; however, legume cover crops increased N2O emissions following their termination. Long-term no-tillage had comparable N2O emissions with conventional tillage, whereas reduced profile-scale soil C storage.</li> </ul> 2) Understand the role of soil biological processes in controlling plant available nitrogen and their relationships with soil health and system resilience. <ul style="list-style-type: circle;"> <li>Project members developed a soil health framework based on agronomic and environmental performance indicators, including crop response to nitrogen. They found that soil management practices such as no-tillage and artificial drainage increase soil N supply and decrease the agronomic optimum nitrogen rate of corn.</li> <li>Poffenbarger and McDaniel contributed to an evaluation of nitrogen indicators of soil health in a study involving long-term research sites in North America.</li> <li>Poffenbarger and Castellano began a project to determine how cover crops and planting date affect N2O emissions from corn and soybean fields.</li> <li>In long-term dryland corn-soybean-wheat systems, cover crop (grass, legume, diverse mixture) effects were evaluated on soil biological health indicators and corn N response.</li> </ul> 3) Translate field and laboratory research into nitrogen management decision-making tools and educational resources promoting improved profitability and sustainability of corn-based cropping systems. <ul style="list-style-type: circle;"> <li>Project members contributed data to a cereal rye biomass database, which is publicly available and can be used to understand factors that affect cover crop productivity.</li> <li>The team members evaluated the performances of various trial design methods and yield response models used to convert on-farm experimental data into nitrogen management decisions.</li> <li>This research group has evaluated DayCent biogeochemical model in predicting crop yield, soil carbon, and N2O emissions in response to long-term tillage, N fertilization, and cover cropping practices.</li> </ul>

Publications

<ol> <li>Published Written Works. Include joint/multistate scientific publications, trade magazine articles, books, posters, websites developed, and any other relevant printed works produced.  Please use the formatting in the examples below. Note: Authors in bold texts indicate the NC1195 committee members</li> </ol> <ul> <li>Huddell A.M. et al., including Poffenbarger, M. Ruark, A. Woodley. 2024. U.S. cereal rye winter cover crop growth database. Scientific Data. 11: 200. <a href="https://doi.org/10.1038/s41597-024-02996-9">https://doi.org/10.1038/s41597-024-02996-9</a></li> <li>Lussich F. et al., including S. Jagadamma, D. Saha. 2024. Cover crop residue decomposition triggered soil oxygen depletion and promoted nitrous oxide emissions. Scientific Reports, 14: 8437. doi.org/10.1038/s41598-024-58942-7</li> <li>Dhaliwal JK. et al., Jagadamma, D. Saha. 2024. Computed tomography scanning revealed macropore-controlled N2O emissions under long-term tillage and cover cropping practices. Science of the Total Environment, 926, 171782. doi.org/10.1016/j.scitotenv.2024.171782</li> <li>Liptzin D. et al., including D. McDaniel, H. Poffenbarger. 2023. An evaluation of nitrogen indicators for soil health in long‐term agricultural experiments. Soil Science Society of America Journal. 87: 868-884. <a href="https://doi.org/10.1002/saj2.20558">https://doi.org/10.1002/saj2.20558</a></li> <li>Yi Q, Curtright A, R. Horwath, X. Zhu-Barker. 2023. Response of soil nitrogen mineralization to warming temperatures depends on soil management history. Geoderma. 440:116716. https://doi.org/10.1016/j.geoderma.2023.116716.</li> <li>Haas SM, R. Horwath, X. Zhu-Barker. 2024. Effects of food waste and green waste composts on yield and nitrogen-use efficiency in irrigated tomato crops. Agronomy Journal, 1-13. <a href="http://doil.irg/10.1002/agj2.21587">http://doil.irg/10.1002/agj2.21587</a></li> <li>Ransom CJ. et al., including FG. Fernández, CAM. Laboski. 2023. Combining corn N recommendation tools for an improved economical optimal nitrogen rate estimation. Soil Science Society of America Journal. 87:902-917.</li> <li>Shao H. et al., including FG. Fernández, CAM. Laboski. 2023. Evaluating critical nitrogen dilution curves for assessing maize nitrogen status across the US Midwest. Agronomy, 13:1948.</li> </ul> <ol start="2"> <li>Scientific and Outreach Oral Presentations. Include workshops, colloquia, conferences, symposia, and industry meetings in which you presented and/or   See below for formatting. Note: Authors in bold texts indicate the NC1195 committee members</li> </ol> <ul> <li>Poffenbarger H. et al., including J. Tomlinson, M.D. Ruark, A. Woodley. 2023. <a href="https://scisoc.confex.com/scisoc/2023am/meetingapp.cgi/Paper/150389">Winter cover crop effects on the optimum n rate of corn and cotton across multi-state field experiments</a>. ASA-CSSA-SSSA International Annual Meeting, St. Louis, MO.</li> <li>Kenneth G.C. et al., including Poffenbarger, M.J. Castellano. 2023. <a href="https://scisoc.confex.com/scisoc/2023am/meetingapp.cgi/Paper/150053">Towards robust, low-cost, quantitative metrics for improving soil health</a>. ASA-CSSA-SSSA International Annual Meeting, St. Louis, MO.</li> <li>Dhaliwal J.K, S. Anderson, J. Lee, S. Jagadamma, D. Saha.  2023.  Computed tomography scanning of intact soil cores revealed macropore-controlled N2O emissions under long-term soil health practices. ASA-CSSA-SSSA International Annual Meeting. St. Louis, MO.</li> <li>Zhu-Barker X, Mirabella, Y. Deng, A.C. von Haden, G.R. Sanford. 2023. Assessing soil N2O emissions and nitrogen dynamics in a corn cropping system receiving processed manure. America Geophysical Union (AGU) Annual Mtg., San Francisco, CA.</li> </ul> <ol start="3"> <li>Fund leveraging, specifically, collaborative grants between stations and members.</li> </ol> Castellano M.J. (PI), A. Margenot, R. Venterea, S. Naeve, M. Salmeron, and H. Poffenbarger. 2024-2025. Reducing nitrous oxide emissions from soybean through early planting and cover crops. United Soybean Board. $1,109,360.

Impact Statements

While N is a critical element of crop production, it is also highly vulnerable to environmental losses contributing to emerging global climate and sustainability issues. Therefore, managing fertilizer N input and soil N cycling is important, although challenging, for sustainable crop production. Such complexity further magnifies under changing climate bringing unpredictable growing season weather conditions as suggested by the team’s research showing corn EONR and yield at EONR can substantially vary due to inter-annual weather variability. Multi-year research conducted by the NC1195 project team members indicated that artificial drainage improves corn yield by 8% while reduced N rate by 16% - drained soils were more beneficial in improving yield and reducing N rate in wetter years. In terms of fertilizer application timing, split application reduced N need, especially in wetter years and undrained soils. Drained soils were $29/ac and $48/ac more profitable than undrained soil under pre-plant and split N application management, respectively. Increasing use of cover cropping and no-tillage as soil health promoting practices influenced corn EONR and soil N cycling. The team’s multiple years of research across different states indicated that legume cover crops before corn did not significantly reduce corn EONR, whereas grass and grass-legume mixture cover crops required more N at EONR.
Research in a dryland corn-soybean-wheat-fallow/cover crop system indicated that cover crops positively influenced soil biological health indicators, especially in the adjacent crop phases after cover crop termination. However, the impact of such improvements in soil biological processes was not realized on corn EONR. Project members investigated alternative N sources such as compost and processed manure as means to reduce reliance on mineral fertilizer N and to understand their impacts on productivity and soil N cycling processes. Separating solids from liquid manure and their subsequent application in corn silage produced improved yield and reduced N2O emissions. Combining green waste compost with mineral N fertilizer consistently reduced N2O emissions across different N fertilization rates. The results are encouraging and will enhance our understanding of how different biologically based alternate N fertilizer products can alter the fate of fertilizer nitrogen. Additionally, it will clarify the agronomic and environmental benefits of applying processed manure and compost.
The research performed by the project members have contributed to: 1) identification of the appropriate on-farm experimental trial designs to translate on-farm data into N management decision; 2) evaluation of process-based biogeochemical model DayCent in predicting crop yield, soil C sequestration, and N2O emissions under long-term tillage and cover cropping practices to inform the utility of such modeling tools to guide sustainable management decisions. Furthermore, the project has generated detailed guideline for farmers and consultants in 1) managing corn N rate, application method (split vs pre-plant), and timing of application considering inter-annual variability in precipitation distribution under drained and undrained systems and provided profitability estimates by reducing N rate and improving yield and 2) evaluating the impact on cover crop integration on corn EONR as influenced by changes in soil biological processes. The findings originated from NC1195 committee member’s research programs have been communicated to both scientific and extension communities through conference presentations, peer-reviewed publications, presentations and training to extension educators and growers’ meetings.