Source: UNIV OF MINNESOTA submitted to NRP
FORAGE LEGUMES AND INTERMEDIATE WHEAT GRASS IN SUSTAINABLE CROPPING SYSTEMS
Sponsoring Institution
National Institute of Food and Agriculture
Project Status
COMPLETE
Funding Source
HATCH
Reporting Frequency
Annual
Accession No.
1010222
Grant No.
(N/A)
Cumulative Award Amt.
(N/A)
Proposal No.
(N/A)
Multistate No.
(N/A)
Project Start Date
Oct 1, 2016
Project End Date
Sep 30, 2021
Grant Year
(N/A)
Program Code
[(N/A)]- (N/A)
Recipient Organization
UNIV OF MINNESOTA
(N/A)
ST PAUL,MN 55108
Performing Department
Agronomy & Plant Genetics
Non Technical Summary
The integration of perennial crops on agricultural landscapes is a solution to many environmental and economic concerns of producers and society. Perennials provide year-round ground cover, often require lower fertilizer and pesticide inputs, and store more soil carbon than annual cropping systems. The use of perennials on agricultural landscapes has declined and new approaches to increase their use by farmers are needed. Alfalfa and intermediate wheatgrass will be studied in field research at multiple locations. The use of new reduced-lignin alfalfa varieties has potential to enhance alfalfa feeding value and increase profitability of alfalfa to producers. We will study their forage yield, forage quality, and persistence response to harvest frequency. We will determine appropriate perennial grasses to plant in binary mixture with reduced lignin alfalfa varieties. Intermediate wheatgrass is a new perennial cereal grain that is being grown in Minnesota. We will determine optimum N rates for grain production, use of legumes to supply nitrogen, approaches to enhance long-term grain yield, and performance of dairy cattle grazing intermediate wheatgrass forage. This research will benefit producers of alfalfa and intermediate wheatgrass and will providing a supply of a new perennial grain for food use.
Animal Health Component
70%
Research Effort Categories
Basic
30%
Applied
70%
Developmental
0%
Classification

Knowledge Area (KA)Subject of Investigation (SOI)Field of Science (FOS)Percent
2051620106050%
2051621106050%
Knowledge Area
205 - Plant Management Systems;

Subject Of Investigation
1620 - Warm season perennial grasses; 1621 - Cool season perennial grasses;

Field Of Science
1060 - Biology (whole systems);
Goals / Objectives
Evaluate the forage yield and forage quality of reduced-lignin alfalfasEvaluate the forage yield and forage quality of reduced-lignin alfalfa in monoculture and in binary mixtures with grassesDetermine optimum N fertilizer rates for intermediate wheatgrass (IWG) grain productionEvaluate nitrogen-fixing legumes to supply N to IWGEnhance long-term persistence of IWG grain yields by between-row disturbancesMeasure effects of cattle grazing of IWG on IWG grain yield and on cattle performance in a fall-grazed IWG grain-forage production system
Project Methods
Objective 1. Evaluate the forage yield and forage quality of reduced-lignin alfalfas Experimental design: randomized complete block with treatments in a split-split plot arrangements with four replicates. Whole plot treatments include three cutting treatments applied in the establishment year. Varieties will be: a) a new high forage digestibility, winterhardy variety (HD); and b) a winterhardy alfalfa variety genetically related to HD except with normal digestibility. Forage yield will be measured in the seeding year and year following seeding by harvesting a 3 by 18 foot area in each plot. Forage quality will be measured by manually taking a sample. Subsamples will be assessed for crude protein, acid detergent fiber, neutral detergent fiber (NDF), and NDF digestibility and mineral concentration. Alfalfa maturity at harvest will be quantified at each harvest. Stand evaluation will be determined by counting plants in 2 ft2 areas in the 4 weeks following seeding and in the fall of the seeding year.Objective 2: Evaluate forage yield and forage quality of reduced-lignin alfalfa in monoculture and in binary stands with grassesExperimental design: randomized complete block with treatments in a split-split plot arrangements with four replicates. Whole plot treatments, which include two cutting treatments based on alfalfa maturity that will be applied beginning in the establishment year: a) cutting to maximize forage yield based on harvests at early flower; and b) cutting to maximize forage quality based on harvest at bud stage. Subplot treatments will be: a) alfalfa grown in monoculture, and in binary mixture with three perennial grasses: b) meadow fescue, c) festulolium, and d) orchardgrass. Sub-subplot treatments will be two alfalfa varieties: a) a new reduced-lignin, high forage digestibility alfalfa; b) a commercial alfalfa cultivar. Plots will be established in April or early May of 2016 by broadcasting inoculated seed and cultipacking into a prepared seedbed. Forage yield and forage quality, alfalfa maturity, and stand evaluation will be collected using procedures described above in Experiment 1. Grass maturity at harvest will be quantified.Objective 3. Optimum N fertilizer rates for intermediate wheatgrass grain production Experimental design will be a randomized complete block with treatments in a split-split plot arrangement and four replicates at each site. Whole plot treatments will be two sources of N fertilizer: urea (conventional fertilizer containing 46% N) or Sustane (an organically approved N fertilizer containing 8% N). Subplot treatments will be five rates of N fertilizer: 0, 20, 40, 60, and 80 lb N/acre. The sub-subplot treatment will be row spacing within plots: 6 or 30 inches between rows. Sub-subplot size will be 6 by 20 feet. An improved IWG variety will be seeded into a weed-free seedbed at a rate of 15 lb/acre. Grain and straw yield measurement: When seeds are mature in August, total yield (grain plus straw) will be measured. We will also measure lodging potential at grain harvest by counting the number of prostrate stems. Straw biofuel determination: To determine biofuel (ethanol) potential of the straw, we will quantify the lignin, cellulose, and cell wall sugars of the biomass. Straw nutritive value evaluation: To determine the value of the harvested straw as a potential livestock feed, we will determine forage crude protein, fiber, in vitro digestibility, and NDF digestibility. Crop enterprise budgets will be developed.Objective 4: Evaluate nitrogen-fixing legumes to supply N to IWG Experimental design will be a randomized complete block. Treatments will include four N-fixing legumes: alfalfa, white clover, Illinois bundle flower, and Canada milk vetch; combined with two intercrop strategies: legumes planted between rows of IWG (36 inches between rows) or broadcast seeded within drilled IWG (6 inches between rows). We will also maintain a control plot without legumes. Plot sizes and methods for measuring grain and straw yields are described above in Objective 3. We will measure legume yields at grain harvest.Objective 5. Enhance long-term persistence of IWG grain yields by between-row disturbances We propose to enhance long-term production of IWG by imposing herbicide and tillage treatments into established IWG stands that are two years old. Experimental design: Randomized complete block with 4 replicates. Treatments will be an untreated control; between-row plant disruptions including herbicide (Roundup) treatment; and mechanical tillage applied in a 30-inch strip in the spring and fall. A row of plants about 6 inch wide will be left. Roundup will be applied using a sprayer equipped with shields to limit the spray drift, and tillage will be applied using a modified rototiller. Treatments will be applied to existing IWG stands in spring and fall of 2016 and yields will be measured in summer of 2016-2018. Methods for measuring intermediate wheatgrass grain and straw yields are described above in Objective 3.Objective 6. Measure effects of cattle grazing of IWG on IWG grain yield and on dairy cattle performance in a fall-grazed IWG grain-forage production system In early September 2016, we will establish stands of IWG (15 lb per acre) and for comparison, a traditional cool season pasture seeded at the West Central ROC at Morris, MN. We will establish by broadcast seeding into a firm, weed free seedbed. We will graze cattle in fall of 2017 beginning in mid-September. Experimental design: Randomized complete block design with 4 replicates. Two treatments are improved permanent pasture and IWG. We will rate lodging and measure grain and straw yields at IWG grain maturity in August 2017. Following IWG grain harvest, the herbage will regrow and in September 2017, livestock will strip-graze (see cattle management). Cattle management: Dairy heifers will graze IWG vegetative regrowth and the improved pasture from mid-September through October. Cattle will be managed using intensive grazing and strip grazing procedures to provide new forage every 48 hours. We will initiate grazing when IWG forage reaches 8-12 inch height at a vegetative stage and graze to a 3-inch height. Animal body weight and body condition score will be measured every 2 weeks. Forage yield and quality: Forage yield will be determined by clipping and weighing biomass prior to grazing. A separate biomass subsample will be ground to pass a 2 mm screen so that forage quality variables can be determined. Forage quality metrics will include crude protein, NDF, NDf digestibility, and in vitro true digestible dry matter. Grain yields: Grain yields for intermediate wheatgrass pastures will be determined in early August when grain reaches physiological maturity. A straw subsample will be dried to determine straw yield. Remaining grain and straw will be machine harvested with a combine and removed from the paddocks.

Progress 10/01/16 to 09/30/21

Outputs
Target Audience:Alfalfa and intermediate wheatgrass producers. Marketers and consultants working with alfalfa and intermediate wheatgrass. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We have provided training opportunities to 8 undergraduate students. How have the results been disseminated to communities of interest?Presentation at conferences: C.C. Sheaffer. 2021. Alfalfa-grass mixtures. Midwest Forage Association Symposium 2021. February 16 2021. Wisconsin Dells, WI 70 attendees. What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? Several experiments were conducted at multiple locations. Experiments had appropriate experimental design and replication. Reduced lignin (RL) alfalfa cultivars produced through genetic modification consistently had herbage with less lignin and greater digestibility that non RL cultivars. Herbage crude protein content and yields were similar for RL and conventional alfalfas. Herbage harvested from an RL alfalfa cultivar had similar amounts of alfalfa protein concentrate in extracted juice as a conventional alfalfa. The feeding value of herbage residue remaining after juice extraction was higher in feeding value for the RL cultivar than for a conventional cultivar. We evaluated the suitability of several perennial grasses for binary mixtures with alfalfa. Perennial ryegrass herbage had lower fiber and greater digestibility than meadow fescue and orchardgrass, but lower herbage yields and stand persistence due to winterinjury. Perennial grasses grown with alfalfa must be evaluated in multiple locations to produce region specific recommendations. We evaluated forage yield, nutritive value, milk production, and persistence of eight alfalfa entries with fall dormancy (FD) ranging from two (FD2) to five (FD5) under cutting frequency of four (CF4), five (CF5) or six (CF6) annual cuts during two production years. Nutritive value of alfalfa forage increased with increased CF and differed among alfalfa entries. At one environment, increasing CF from CF4 to CF5 and from CF5 to CF6 caused a 5% and a 29% decrease in milk/ha, respectively. At another environment, CF5 had about 16% greater milk production than CF4 and CF6. The CF6 reduced third-year stand density with the effects especially severe for some entries. Alfalfa entry FD was not correlated to forage yield or persistence, but an entry with FD5 was consistently among those with the greatest forage and milk yield ha-1 at CF5 and CF6. To prevent IWG grain yield decline that normally occurs with increased IWG stand age, inter-row cultivation using rotary-zone tillage as well as herbicide, burning, and mowing at different times were employed for two years, but no treatment effectively prevented grain yield decline. However, the application of herbicide in spring versus fall had positive and negative implications (relative to other management treatments) for grain and straw yield, respectively. We evaluated perennial legume intercropping with IWG as an approach to supply N fertility and prevent IWG grain yield decline with stand age. Alfalfa, red clover, and birdsfoot trefoil had the highest legume biomass yields while Canada milkvetch and white clover had the lowest yields. Nitrogen transfer rates from the legume to IWG ranged from 0 to 27% of the N in IWG herbage with differences due to soil fertility. Trade-offs were observed between high yielding legume intercropping treatments like alfalfa, which tended to result in lower IWG grain yields, and low-yielding legumes, such as white clover, which tended to result in higher grain yields. Intercropping with perennial legumes did not affect grain yield decline compared with mineral N fertilization. Ultimately, if a legume intercrop system is designed for a specific site with an appropriate species, it can produce grain yields similar to those produced by moderate levels of mineral fertilizer. Fertilizing IWG with a single application of 80 kg N ha-1 in the spring increased grain, shoot, and root tissue N concentration compared to an unfertilized control. Shoot tissue N content declined between anthesis and grain physiological maturity, and root tissue N concentration declined between spring vegetative regrowth and grain physiological maturity, suggesting a reallocation of N to grain tissue leading up to reproductive maturity. Root N concentration did not increase between grain harvest and fall dormancy, suggesting that no translocation of N occurred during the fall. Straw and hay production can affect the profitability of a IWG production system. Average spring and fall forage yields ranged from 1.1 to 2.8 Mg/ha, respectively. Relative feed value (RFV), an index describing energy intake, averaged 154 and 93 for spring and fall forage, respectively. Straw yields resulting from grain harvest were 3-4 times higher than hay yields and had a RFV of 64. Consistently highest net returns were achieved by harvesting grain and straw in summer, and hay in the fall. Fall forage produced by IWG can also be harvested by grazing livestock. Dairy heifers sequentially grazed paddocks of an IWG-alfalfa mixture in a strip grazing design from October to November following grain and straw harvest in August. Average daily gain by heifers grazing an IWG-alfalfa mixture averaged .50 kg/day in 2018 and .60 kg/day in 2018. Forage yield at the initiation of grazing in October 2107 and 2018 was about 1800 and 1000 kg/ha, respectively; and declined 10 kg/ha and 3 kg/ha, respectively, from October to November for each GDD following initiation of grazing. Fall grazing in 2017 was associated with higher grain yields in 2018, but grazing in 2018 had no effect on grain yields in 2019.

Publications

  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Prigge, J. L., Sheaffer, C. C., Jungers, J. M., Jaqueth, A. L., Lochner, H. L., and Martinson, K. L. 2021. Forage characteristics and grazing preference of cover crops in equine pasture systems. J. Equine Veterinary Sci., 103. 103:103663 doi: 10.1016/j.jevs.2021.103663
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Jungers, J. M., Yang, Y., Fernandez, C. W., Isbell, F., Lehman, C., Wyse, D., and C. Sheaffer, 2021. Diversifying bioenergy crops increases yield and yield stability by reducing weed abundance. Science Adv, 7(44). doi: 10.1126/sciadv.abg8531
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Wiering, N.P., N.J. Ehlke, D. Catalano, K. Martinson, and C. C. Sheaffer. 2021. Forage potential of winter-hardy perennial ryegrass populations in monoculture and binary alfalfa mixture. Agron. J. 2021:5483-5195. Doi:10.1002/agj2.20837
  • Type: Journal Articles Status: Published Year Published: 2021 Citation: Coburn, J., M.S Wells, C.C. Sheaffer, R. Ruan, and D. A. Samac. 2021. Comparison of plant feedstocks and methods to recover leaf proteins from wet fractionation of alfalfa for potential use in aquaculture, poultry, and livestock feeds. Agrosystems, Geosciences and Environment. 4, no. 2 (2021): e20184 http://doi.org/10.1002/agg2.20184


Progress 10/01/19 to 09/30/20

Outputs
Target Audience:Dairy and beef producers who feed alfalfa and forages as a component of the dairy ration and who benefit from a high-quality hay or haylage and field management flexibility. Intermediate wheatgrass producers who grown the new crop. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We have employed graduate students and undergraduate students on the project. How have the results been disseminated to communities of interest?Results have been disseminated at workshops with producers. Intermediate wheatgrass results have been reported at the International Kernza conference. In addition, intermediate wheatgrass results have been incorporated into a grower's guide publication. What do you plan to do during the next reporting period to accomplish the goals?We will complete statistical analysis of data and publish the results of research on use of nitrogen-fixing legumes to supply N to intermediate wheatgrass, and we will measure the effects of cattle grazing of intermediate wheatgrass in the fall and spring on intermediate wheatgrass grain and forage yields. We will complete studies of intermediate growth and development.

Impacts
What was accomplished under these goals? In testing of widely marketed alfalfa cultivars in the seeding and first production year in Minnesota and New York, forage yield was similar for genetically modified reduced lignin (RL) and non-RL cultivars. Relative to control non-RL cultivars, lignin was 13% lower and neutral detergent fiber digestibility (NDFD) was 5% higher in RL cultivars. Lignin and neutral detergent fiber increased and crude protein and NDFD digestibility decreased with increasing growing degree days at a similar rate for both reduced lignin and control non-RL control. We found that feeding of hay produced from RL forage altered the microbial populations in the horse digestive system. Nitrogen application at rates of 80 kg ha-1 had no effect on grain yield compared to the non-fertilized control in the first production year (year 1), but increased yields in years 2 and 3. Reducing planting density from 145 to 36 seeds m−2reduced grain yield in year 1 but increased grain yield in subsequent years, particularly when coupled with N fertilizer applied at 80kg N ha−1. Intermediate wheatgrass grain yield response to increasing N rates was similar when fertilized with synthetic or organic fertilizers. A high proportion of fertile tillers was the best predictor of high IWG grain yield, suggesting that shifts toward vegetative growth over sexual reproduction in the years following establishment are associated with grain yield declines. Biomass yield responded positively to increasing N application rates from 0 to 80 kg ha-1 and increased planting density. Defoliation of vegetation in spring and fall and planting in wider row spacing (15 vs. 61 cm between rows) increased tillers ha-1, reduced lodging, and maximized grain yields over a 4-yr stand life. Neither defoliation nor row spacing prevented grain decline from 880 kg ha-1 in year 1 to 280 kg ha-1 in year 4. Defoliation in spring and fall reduced hay and straw yields. Hay and straw yields were greater in 15- and 30-cm rows than in 61-cm rows. Net economic returns were greatest with narrow rows and with fall cutting of intermediate wheatgrass forage for hay. Based on local hay auction pricing, straw remaining following grain harvest was more valuable than hay. Inter-row cultivation using rotary-zone tillage (RZT) as well as herbicide, burning, and mowing at different times were employed for two years, but none effectively prevented grain yield decline as stand aged.

Publications

  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Catalano, D.N., C.C. Sheaffer, N.P. Wiering, A.M. Grev, N.J. Ehlke, E. Mousel, K.L. Martinson. 2020. Yield, persistence, forage nutritive value, and preference of perennial ryegrass under grazing. Agron. J. 112: 4182-4194. DOI: 10.1002/agj2.20364
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: DeBoer, M.L, A.M. Grev, C.C. Sheaffer, M.S. Wells, K.L. Martinson. 2020. Herbage mass, botanical composition, forage nutritive value, and preference of grass-legume pastures under horse grazing. Crops, Forage, & Turfgrass Mgt. 2020;6:e20032. https://doi.org/10.1002/cft2.20032
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Fernandez, C. W., N. Ehlke, C. C. Sheaffer, J. M. Jungers. 2020. Effects of nitrogen fertilization and planting density on intermediate wheatgrass yield. Agron. J. 112: 4159-4170 https://doi.org/10.1002/agj2.20351
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Grev, A. M., M. S. Wells, D. N. Catalano, K. L. Martinson, J. M. Jungers, C. C. Sheaffer. 2020. Morphology and stem and leaf forage nutritive value of reduced lignin alfalfa. Agron. J. 112:406-417.
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Gomez, A., A.K. Sharma, A. Grev, C. Sheaffer, KI. Martinson. 2020. The horse gut microbiome responds to a highly individualized manner to forage lignification. J. Equine Vet. Sci. https://doi.org/10.1016/j.jevs.2020.103306
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Hunter, M. C., C. C. Sheaffer, S. Culman, J. M. Jungers. 2020. Effects of defoliation and row spacing on intermediate wheatgrass I: Grain production. Agron. J. 113:1748-1763.
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Hunter, M. C., C. C. Sheaffer, S. Culman, W. Lazarus, J. M. Jungers. 2020. Effects of defoliation and row spacing on intermediate wheatgrass II: Forage yield and economics. Agron. J. 113:1862-1880.
  • Type: Journal Articles Status: Accepted Year Published: 2020 Citation: Jungers, J., J. Cherney, K. Martinson, A. Jaqueth, C. Sheaffer. 2020. Forage nutritive value of modern alfalfa cultivars. Crop, Forage, & Turfgrass Mgt. https://doi.org/10.1002/cft2.20076
  • Type: Conference Papers and Presentations Status: Accepted Year Published: 2020 Citation: J. Jungers, M. Hunter, S. Culman, B. Lazarus, C. Sheaffer. 2020. Dual-Use Potential of Intermediate Wheatgrass  Forage and Grazing. 4rd Annual International Kernza Conference  Virtual. July 2020.


Progress 10/01/18 to 09/30/19

Outputs
Target Audience:Dairy, and beef producers who feed alfalfa and forages as a component of the daily ration and who will benefit from a higher quality hay or haylage and field management flexibility. Intermediate wheatgrass producers who grow the new crop Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?We have employed post PhD students on the project to participate in the research. We have employed undergrad interns on the project to assist the technician. How have the results been disseminated to communities of interest?We have conducted education events that directly contact the target audiences. We have developed news releases about our research. What do you plan to do during the next reporting period to accomplish the goals?We will continue to conduct field research and develop research and outreach materials.

Impacts
What was accomplished under these goals? Field research was completed that showed that changes in forage nutritive value for reduced lignin alfalfa are largely a result of changes in ADL and NDFD within the stem fraction, and confirm that alfalfa forage nutritive value is negatively affected by forage maturity, particularly within the stem portion of the plant. We grew reduced lignin alfalfa with festolium, meadow fescue and orchardgrass. We found that reduced-lignin alfalfa averaged between 11.0 and 18.5% less lignin over the three years and averaged between 5.8 and 10.6% greater NDFD, compared to a reference variety. Alfalfa nutritive value response was relatively consistent across regions, but grass response was variable across regions for both grass proportion in mixtures and nutritive value. Perennial grasses grown with reduced lignin alfalfa must be evaluated for both yield and nutritive value on a regional basis to produce meaningful results. Research is continuing on evaluating optimum fertilizer rates for intermediate wheatgrass, use of nitrogen fixing legumes to supply N to intermediate wheatgrass and on inter row disturbances. We have found that grain yield declines in the years following establishment remains a major challenge to the profitability of IWG as a perennial grain crop. Higher N application rates helped mitigate these declines in the years following establishment but ultimately these increases due to fertilization were relatively small. Our results suggest that plant density is a major factor reducing grain yields in IWG. While wider row spacing was beneficial to grain yield in the second year, these effects were minor and the lower plant densities severely limited grain production the first year. The yield component that best explained the decline in grain yield with stand age was the proportion of fertile tillers, which was not strongly affected by manipulating N fertility or row spacing. Overall, our results indicate that there is potential to produce a substantial quantity of high-quality forage biomass with spring and fall clippings or grazing, up to 1.2 tons per acre, without reducing Kernza grain yield. Harvesting biomass in both spring and fall resulted in the highest yield. Grain yields averaged from 70-350 lb/acre.

Publications

  • Type: Journal Articles Status: Accepted Year Published: 2019 Citation: Cherney, J. H.; R. Smith; C. Sheaffer; D. J. Cherney 2019. Nutritive value and yield of reduced-lignin alfalfa cultivars in monoculture and in binary mixture with perennial grass. Agron. J. doi: 10.2134/agronj2019.05.0348
  • Type: Journal Articles Status: Accepted Year Published: 2019 Citation: A. Gomez, A. Grev, R. Mottet, M. Hathaway, C. Sheaffer, K. Martinson. 2019. Feeding reduced lignin alfalfa hay modulates the horse fecal microbiome in an individualized manner. J. Equine Vet. Sci. 76:43-53.
  • Type: Journal Articles Status: Accepted Year Published: 2019 Citation: Catalano, D.N., C.C. Sheaffer, A.M. Grev, M.L. DeBoer and K.L. Martinson. Yield, forage nutritive value, and preference of legumes under horse grazing. Agronomy J. 111: 3: 1312-1322 doi:10.2134/agronj
  • Type: Journal Articles Status: Accepted Year Published: 2019 Citation: Jungers, J. M., R. Noland, D. E. Kaiser, D. A. Samac, J. A. Lamb, M. S. Wells, J. F. S. Lamb, and C. C. Sheaffer. 2019. Potassium fertilization affects alfalfa forage yield, nutritive value, root traits, and persistence. Agronomy Journal. 111. doi:10.2134/agronj2019.01.0011
  • Type: Journal Articles Status: Accepted Year Published: 2019 Citation: Jungers, J. M., L. R. DeHaan, D. J. Mulla, C. C. Sheaffer, D. L. Wyse. 2019. Reduced nitrate leaching in a perennial grain crop compared to maize in the Upper Midwest, USA. Agriculture, Ecosystems and Environment. 272:63-73.
  • Type: Journal Articles Status: Awaiting Publication Year Published: 2019 Citation: Grev, A.M., M. S. Wells, D. N. Catalano, K L. Martinson, J M. Jungers, and C. C. Sheaffer. 2019. Stem and leaf forage nutritive value and morphology of reduced lignin alfalfa. Agronomy J. 111


Progress 10/01/17 to 09/30/18

Outputs
Target Audience:Target Audience includes alfalfa growers, alfalfa seed retailers, intermediate wheatgrass seed producers and seed processers, state agencies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Three undergraduate students received training in field research with alfalfa and intermediate wheatgrass. These experiences included research on establishment, crop harvest, and data collection. Two graduate students were provided advanced experience in establishing research objectives, experimental design, conducting research, and statistical analysis of data. Graduate students had opportunity to present results of their research at professional and grower meetings. How have the results been disseminated to communities of interest?Meetings and workshops with growers and professionals. What do you plan to do during the next reporting period to accomplish the goals?Research related to objectives 3-6 will continue using existing plots previously established. Perennial crops like alfalfa and intermediate wheatgrass are typically harvested for multiple years. As part of these experiments, we will complete an economic analysis of the results.

Impacts
What was accomplished under these goals? Reduced lignin alfalfa (Medicago sativa L.) has the potential to improve alfalfa forage quality and increase farm profitability yet forage morphology and stem and leaf nutritive value remains undetermined. Reduced lignin and reference alfalfa cultivars had similar stem and leaf yield, leaf to stem ratio (L:S) and leaf forage nutritive value. On average, the reduced lignin alfalfa had a 13% decrease in stem acid detergent lignin (ADL) and an 11% increase in stem NDF digestibility (NDFD) compared to a conventional reference cultivar. Forage nutritive value within stem and leaf fractions is affected by forage maturity, particularly within the stem portion of the plant. 2. Alfalfa is frequently grown in mixture with grasses. This research assessed the yield and nutritive value of reduced-lignin alfalfa vs. a standard reference alfalfa when both were grown in monoculture and binary mixtures with three perennial grasses (festulolium, meadow fescue, and orchardgrass). Mixed alfalfa-grass stands had similar yields as alfalfa grown in monoculture. Winterinjury limited the productivity of the grasses except for orchardgrass. 3. Lodging is an important factor negatively affecting intermediate wheatgrass grain yields. The plant growth regulator Trinexapacethyl consistently reduced plant height and lodging by up to 20%. 3. We measured water quality and crop yields beneath IWG, maize, and switchgrass under three N fertilizer treatments; low N (0 kg N ha−1), medium N (maize = 80, switchgrass and IWG = 40 kg N ha−1), and high N (maize = 160, switchgrass and IWG = 120 or 160 kg N ha−1). The switchgrass and IWG medium N treatments also included alfalfa as an intercrop. The NO3-N concentration in soil solution 50 cm below the surface was one and two orders of magnitude lower in high N fertilized IWG compared to switchgrass and maize, respectively. Soil solution NO3-N increased with N fertilizer in all crops. Using the Denitrification and Decomposition (DNDC) model, average annual NO3-N leaching estimates in the high N treatments were 21.7 kg N ha−1 for maize and 3.7 and 0.2 kg N ha−1 for switchgrass and IWG, respectively. 4. Intermediate wheatgrass was established at five environmentally diverse sites in bi-culture with alfalfa and in monoculture fertilized annually in the spring with 80 kg N/ha. Across all sites, IWG grain yield decreased 80% in the fertilized monoculture and 65% in the bi-culture with alfalfa from year 2 to 4. In year 4, IWG grain yield was similar or greater in the bi-culture than the fertilized monoculture at three of the five sites and alfalfa biomass was correlated positively with grain yield, harvest index and nutrient uptake in the year 4 bi-culture. 5. Inter- row disturbances using tillage, herbicides, and burning have been unable to maintain intermediate wheatgrass grain yields over years. 6. Dairy cattle have successfully grazed intermediate wheatgrass from September to November and cattle have had performance similar to traditional cool season forage grasses.

Publications

  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Frahm, C.S., Tautges, N., Jungers, J.M., Ehlke, N., Wyse, D.L., and C. C. Sheaffer. 2018. Responses of intermediate wheatgrass to plant growth regulators and nitrogen fertilizer. Agron. J. 110:1028-1035.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Jungers, J. M., L. R. DeHaan, D. J. Mulla, C. C. Sheaffer, and D. L. Wyse. 2018. Reduced nitrate leaching in a perennial grain crop compared to maize in the Upper Midwest, USA. Agric., Ecosystems Environment. 272:63-73.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Jungers, J.M., Frahm, C.S., Tautges, N., Ehlke, N., Wells, M.S., Wyse, D.L., C. C. Sheaffer. 2018. Growth, development, and biomass partitioning of the perennial grain crop Thinopyrum intermedium. Annals Applied Biol. 172:346-354.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Tautges, N., J. M. Jungers, L. DeHaan, D. Wyse, C. C. Sheaffer. 2018. Maintaining grain yields of the perennial cereal intermediate wheatgrass in monoculture vs. biculture with alfalfa in the Upper Midwestern U.S. J. Agric. Sci. 156:758-773.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Goplen , J. J., J A. Coulter, C. C. Sheaffer, R. L. Becker, F. R. Breitenbach, L M. Behnken, and J. L. Gunsolus. 2018. Economic performance of crop rotations in the presence of herbicide-resistant giant ragweed. Agron. J. 110: 260-268 doi:10.2134/agronj2016.09.0536
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Goplen, J.J., C.C. Sheaffer, R.L. Becker, R.D. Moon, J.A. Coulter, F.R. Breitenbach, L.M. Behnken, and J.L. Gunsolus. 2018. Giant ragweed (Ambrosia trifida) emergence model performance evaluated in diverse cropping systems. Weed Sci. 66:3646. doi: 10.1017/wsc.2017.38.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Goplen, J.J., C.C. Sheaffer, R.L. Becker, J.A. Coulter, F.R. Breitenbach, L.M. Behnken, and J.L. Gunsolus. 2018. Giant ragweed emergence pattern influenced by spring tillage timing in Minnesota. Crop, Forage & Turfgrass Mgt. 4:180025.doi:10.2134/cftm2018.04.0025
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Noland, R.L., M.S. Wells, J.A. Coulter, C.C. Sheaffer, K.L. Martinson, J. Baker, and T. Tiede. 2018. Estimating alfalfa yield and nutritive value using remote sensing and air temperature. Field Crops Research. 222: 189-196.
  • Type: Journal Articles Status: Published Year Published: 2018 Citation: Wiering, N.P., C. Flavin, C.C. Sheaffer, G. C. Heineck, W. Sadok, and N. J. Ehlke. 2018. Winter hardiness and freezing tolerance in a hairy vetch collection. Crop Sci. 58: 1594-1604 doi:10.2135/cropsci2017.12.0748.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2018 Citation: Grev, A.M., M.S. Wells, D.N. Catalano, K.L. Martinson, and C.C. Sheaffer. 2018. Quantifying morphological development and forage nutritive value of stem and leaf fractions for reduced lignin alfalfa. In Proceedings: American Forage and Grassland Council 2018 Annual Meeting. Louisville, KY. Available online at http://www.afgc.org/ proceedings/2018/ES_Amanda_Grev.pdf


Progress 10/01/16 to 09/30/17

Outputs
Target Audience:target audience include alfalfa growers, alfalfa seed retailers; intermediate wheatgrass seed producers and seed processers, state agencies interested in water protection. These groups were reached through field days and publications. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?Three undergraduate students received training in field research with alfalfa and intermediate wheatgrass. These experiences included research on establishment, crop harvest, and data collection. Two graduate students were provided advanced experiences in establishing research objectives, experimental design, conducting research, and statistical analysis of data. Graduate students had opportunity to present results of their research at professional and grower meetings. How have the results been disseminated to communities of interest?Meetings and workshops with growers and professionals. What do you plan to do during the next reporting period to accomplish the goals?Research related to objectives 2-6 will continue using existing plots previously established. Perennial crops like alfalfa and intermediate wheatgrass are typically harvested for multiple years. As part of these experiments, we will complete an economic anlaysis of the results.

Impacts
What was accomplished under these goals? Impact; For both alfalfa (1 and 2) and intergediate wheatgrass goals (3-6), the long-term objective is to increase crop diversity on agricultural landscapes with perennial crops that provide ecosystem services as well as economic return. Reduced-lignin alfalfa research will provide growers with a new managment tool: a change in knowledge occurred by first publication of results showing the advantages of reduced lignin alfalfas to provide to alfalfa producers opportunities for decision making flexibility in alfalfa management. Intermediate wheatgrass research will provide a change in knowledge and action by producers and public agencies who are producing seed of intermediate wheatgrass for human consumption and who are adopting use of intermediate wheatgrass for use in surface and ground water improvement. This has led to intermediate wheatgrass plantings at well-head protection sites which will ultimately lead to improvement in availablity of safe water with lower levels of nitrate nitrogen and in improvement of soil health. 1. Forage yield and quality of reduced-lignin alfalfas: Completed experiments at 4 locations on new reduced lignin alfalfas and published the results. Data collected for forage yield forage quality, and stand persistence. A reduced lignin alfalfa had an average of 5% less lignin and 10% greater cell walll digestibility than reference varieties. First peer reviewed publication showing advantages of the new reduced lingin alfalfas. 2. Reduced-lignin alfalfa in monoculture and in grass mixture: Experiments ongoing at 2 locations. Data collected for forage yield and forage quality analysis, statistical analysis of results is ongoing and outcomes are unknown. 3). Optimal N fertilizer rates for intermediate wheatgrass (IWG). Experiments ongoing at 3 locations evaluating the effect of 5 N fert rates . Data collected for grain and straw production during first year of production. A nitrogen fertilizer rate of 60-80 lb per acre is biologically optimum. New knowledge is provided to intermediate wheatgrass grain growers. 4. Legumes for binary mixture with IWG. Experiments conducted at two locations. Data collected on botanical composition of the mixtures, grain and straw yields in the first 2 years following seeding; additional years of research will be conducted. Alfalfa was the best legume for growth with IWG but reduced IWG yields. Growth of IWG with legumes resulted in lower grain yields then when IWG was grown in monoculture and fertilized with N. 5. Enhancing long-term persistence of IWG grain yields. Experiment being conducted for 2 years and grain yields measured. Interrow disturbance with tillage resulted in grain yields of 100 kg/ha whereas the non-distured control had yields of nearly 150 kg/ha. Treatment with a herbicide (Glyphosate) reduced yields to about 60 kg/ha. 6. Cattle grazing of IWG. A trial was initiated with 1 year old stands of IWG being grazed by cattle. IWG forage yields were 250 kg/ha in the spring and 2500 kg/ha in the fall. IWG grain yields were about 400 lb per acre and a spring harvest did not affect grain yields. Grazing controlled weeds and did not affect IWG stands.

Publications

  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Grev., A.M., M. S. Wells, D. A. Samac, K.L. Martinson, and C. C. Sheaffer. 2017. Forage accumulation and nutritive value of reduced lignin and reference alfalfa cultivars. Agron. J. 109:1-13. Doi:10.2134/agronj2017.04.0237
  • Type: Journal Articles Status: Published Year Published: 2017 Citation: Jungers, J. M., L. DeHaan, K. Betts, C. C. Sheaffer, D. L. Wyse. 2017. Intermediate wheatgrass grain and forage yield responses to nitrogen fertilization. Agron. J. 109:462-472.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Grev, A.M., M.S. Wells, C.C. Sheaffer, and K.L. Martinson. 2017. A comparison of reduced lignin and conventional alfalfa varieties and their potential for use as equine forage sources. J. Equine Vet. Sci. 52:100.
  • Type: Conference Papers and Presentations Status: Published Year Published: 2017 Citation: Jungers, J.M., L. DeHaan, D. Mulla, C. Sheaffer, D. Wyse. Limited nitrate leaching beneath intermediate wheatgrass. 2017. ASA, CSSA, and SSSA Annual Meeting.
  • Type: Other Status: Published Year Published: 2017 Citation: Sheaffer, C.C., S. Wells, J. Larson. 2017. Minnesota Variety Trial results: Alfalfa. Minnesota Agric. Exp. Stn. MP 113-2017.