Location: Forage and Livestock Production Research2017 Annual Report
The long-term objectives of this project are to develop improved techniques that will enhance ecological function and efficiency of resource use in prairie and pastureland, increase forage productivity, and promote sustainability of livestock production systems in the Southern Great Plains. Specifically, during the next five years we will focus on the following: Objective 1: Enhance productivity and ecological function of native tall-grass prairies by development of management practices, including management-intensive grazing, and restoration strategies to follow invasive brush and tree species removal. Sub-objective 1A: Compare the effects of different systems of intensive grazing on plant communities and soil properties of over-utilized tallgrass ecological sites, and define shifts in responses to applied management regimes. Sub-objective 1B: Determine greenhouse gas emissions from soil, plant, and animal components of diverse grazing systems. Sub-objective 1C: Define the influence of eastern redcedar trees on local soil conditions of abandoned cropland (old fields), and identify restoration practices that enhance conversion of retrogressed old fields to native prairie. Objective 2: Increase sustainability in grazing systems and improve year-round availability of forages for grazing through: improved pasture establishment and persistence, use of multipurpose legume crops, reduced need for purchased inputs in crop and forage production systems, and increased efficiency of water and nitrogen use. Sub-objective 2A: Assess effect of tissue damage on grass growth, development, and persistence characteristics. Sub-objective 2B: Identify forage species and management practices, including use of legume crops for green manure, that promote efficiency of resource use, especially N and water use, to increase year-round availability of forage for grazing. Objective 3: Increase marketing options, including providing high-quality farm-finished beef, through development of management systems that optimize on-farm feed resources and minimize the need for external inputs. Sub-objective 3A: Identify and evaluate forage resources for efficacy at critical times in the production cycle for farm-finished beef of different genetic types. Objective 4: Provide decision-support tools to aid land managers in evaluating climatic risks and ecologic and economic outcomes in selecting production and conservation practices and strategies for grazingland ecosystems. Objective 5: Develop improved cool-season grasses and legumes to improve productivity and sustainability of grazing and crop lands in the Southern Great Plains. Sub-objective 5A: Develop tools to support selection of improved cultivars. Sub-objective 5B: Identify germplasm of perennial cool-season grass forages adapted to heat, drought, and nutrient stresses of the Southern Great Plains.
Livestock production systems in the Southern Great Plains are confronted with problems of limited and uncertain forage supply, increased climatic variability, and environmental degradation that threaten economic viability and system sustainability. This project will develop management practices and identify forage genotypes that are resilient under variable climate and will increase forage productivity and input use-efficiency on livestock farms at a range of scales. Commensurate with the scope of the location as a Long-Term Agroecosystem Research network site, we will initiate assessments of greenhouse gas (GHG) emissions and agricultural production under different livestock systems of the Southern Great Plains, including both native prairie and wheat pasture. Data from this study will be pooled with results from similar flux studies in the region to evaluate climate and environmental impacts on system response. To evaluate system resilience, over-utilized prairie ecological sites with a mix of native and introduced species indicative of good and poor condition mixed grass prairie will be used to evaluate the use of infrequent, high-intensity grazing on succession and diversity of forage species at the sites. The impact of prior encroachment of redcedar on old-field nutrient and seedbank reserves and consequent recovery of understory and grass species following removal of redcedar will be assessed. The use of legumes and grasses as green manure sources will be researched for summer (sorghum) and winter (wheat) grain crops to promote efficiency of N and water use. Nitrogen turnover and utilization by the subsequent crop will be assessed. Also, N-uptake and efficiency of utilization of cool-season annual and perennial species will be measured in greenhouse experiments to develop screening methods for plant germplasm. Improved management methods will be developed to fully utilize the genetic potential of new cultivars by enhancing establishment, yields, and utilization by livestock. To increase marketing options of livestock producers, we will determine appropriate forage resources for production of farm-finished beef, either on all forage or with limited grain inputs. Interactions of animal genetic type (frame score) and finishing system (forage or grain) will be assessed. Time-series data from ryegrass trials in four southern states in the last decade will serve as the basis for examining the possible importance of 5-day and 7-day summary weather statistics of the near-surface environment, and the variations of those statistics around decade-long averages, as a predictor for seasonal production. Plant breeding technologies will be used to develop improved cultivars of perennial C3 grasses, particularly fescue, that are more persistent under the regional climatic conditions, and are more water-use efficient. Basic molecular biology and biochemistry/physiology information will be developed that will improve plant breeding techniques and products.
Research scientist staffing through the reporting period was approximately 3.75 SY, or 62%, of the 6.0 SY required to execute the project plan. In consequence, progress in most components of the project was significantly hindered during FY17. In those areas where staffing and resources were adequate, implementation of the project proceeded as limited available resources allowed. A series of factsheets describing results of completed and ongoing forage and livestock production research carried out under this project and its immediate predecessors were presented at the October 2017 Grazinglands Research Laboratory (GRL) Field Day. As part of a broader study defining responses of native tall-grass prairie to grazing management (Objective 1A.), sample analyses and statistical analyses of data pertaining to soil nutrients was completed. This study defined how grazing management affected levels of flux for a suite of plant-essential macro-nutrients in rangeland soil using a novel membrane-based device developed for croplands in Canada. Enteric methane production measured in cow herd grazing native pasture was measured (Objective 1B). Approximately 3 full years of enteric methane production by the cow herd has been collected. Another intensive campaign collection was conducted in February of 2017. As part of a broader study of greenhouse gas emissions from grasslands (Objective 1B.), production of carbon dioxide and water flux was examined for tame warm-season perennial grasslands under different forms of management, and different row crops grown within agricultural production systems, were reported in scientific journals. Greenhouse studies (Objective 2B.2), delayed by 2013 furlough, and refurbishment and improvement of greenhouse infrastructure (completed in FY15) were conducted to define allocation of biomass and nitrogen to aboveground and belowground components of annual legumes during the reporting period. Data were collected from a field experiment (Objective 2B.4) established in 2015 [delayed two years because the critical planting period was missed due to government shut-down (October 2013), and loss of experimental sites due to closure of participating location] investigating the value of fall or spring sown legumes as green manure to supply nitrogen for warm-season grass. Establishment of cow herds to support the farm-finished beef program (Objective 3) continued during the reporting period. Calves produced during 2016 are currently on finishing treatments and carcass data will be collected at finishing weights in the coming months. An experiment initiated in 2015 to evaluate the impact of early season grazing of burned native pasture on stocker and pasture productivity continued. The third year of an experiment (Objective 3) that grazed alfalfa as a component of production systems used to produce forage finished beef was undertaken. Animal performance metrics were measured, and forage samples collected to define quality attributes of grazed pastures. The second year of an experiment (Objective 3) that utilizes annual spring burns to extend the grazing season of stocker cattle, to produce forage-finished beef using combinations of cool and warm-season forage was completed. Animal performance metrics were measured, and forage samples collected to define quality attributes of grazed pastures. New tall fescue and orchardgrass synthetics began evaluation for forage quality and agronomic traits (Objective 5A) near Mound Ridge, Kansas. Patent applications were submitted and accepted by the Office of Technology Transfer for: A method for seed production of self-incompatible dihaploid tall fescue; and a method for the production of haploid Lolium sp. A series of studies (Objective 5B) resulted in: a drought-tolerant smooth bromegrass cultivar named ‘Artillery’ and a drought-tolerant tall fescue named ‘Armory’, received a Plant Variety Protection and have been licensed to cooperator through the Office of Technology Transfer; A selection cycle for a developing drought-tolerant orchardgrass entered its third cycle of selection for persistence, drought tolerance and adaptability to the Southern Plains Region; The first year of Plant Variety Protection data acquisition for an ‘Oklahoma Creeping Wheatgrass Hybrid” was completed. A cooperator has indicated a desire to license and market this hybrid following previous years of performance testing.
1. Release of ‘Artillery’ smooth bromegrass. Adapted and tolerant cool-season, perennial grass forages are required in the Southern Plains Region of the U.S. to fill spring and fall forage deficits for grazing livestock. ARS researchers at the Grazinglands Research Laboratory, El Reno, Oklahoma obtained plant variety protection and a license for the commercialization and marketing of the smooth bromegrass cultivar in 2016. The release of this cultivar fills a need for cool-season, perennial grass forage germplasm for grazing under low nitrogen, dryland conditions.
2. Patent application for a “Lolium multiflorum line that Induces Genome Loss”. Adapted and tolerant cool-season, perennial grass forages is required in the Southern Plains Region of the USA to fill spring and fall forage deficits for grazing livestock. ARS researchers at the Grazinglands Research Laboratory, El Reno, Oklahoma developed a novel approach for generating superior genotypes of tall fescue and its related species utilizing a novel ryegrass. The research resulted in the submission of the third of three U.S., Australian, and European Union patent applications for the technology. The release of the materials and patent provide a new and efficient approach for the superior breeding of adapted fescue germplasm.
Kindiger, B.K. 2016. Generation of paternal dihaploids in tall fescue. Grassland Science. 62:243-247.
Araya, A., Kisekka, I., Gowda, P. 2016. Evaluation of water-limited cropping systems in a semi-arid climate using DSSAT-CSM. Agricultural Water Management. 150:86-98.
Zhou, Y., Xiao, X., Wagle, P., Bajgain, R., Mahan, H., Basara, J., Dong, J., Qin, Y., Zhang, G., Luo, Y., Gowda, P.H., Neel, J.P., Steiner, J.L., Starks, P.J. 2017. Examining the short-term impacts of diverse management practices on plant phenology and carbon fluxes of Old World bluestems pasture. Agricultural and Forest Meteorology. 237:60-70. https://doi.org/10.1016/j.agrformet.2017.01.018.
Wagle, P., Bhattarai, N., Gowda, P., Kakani, V. 2017. Performance of five surface energy balance models for estimatng daily evapotranspiration in high biomass sorghum. Journal of Photogrammetry and Remote Sensing. 128:192-203.
Wagle, P., Gowda, P., Anapalli, S.S., Northup, B.K., Reddy, K.N. 2017. Growing season variability in carbon dioxide exchange of irrigated and rainfed soybean in the southern United States. Science of the Total Environment. 593-594:263-273.
Bartholomew, P.W. 2015. Seed size effects on early seedling growth and response to applied nitrogen in annual ryegrass (Lolium multiflorum L.). Agricultural Sciences. 1232-1238.
Kisekka, I., Schlegel, A., Ma, L., Gowda, P., Vara Prasad, P. 2017. Optimizing preplant irrigation for maize under limited water in the high plains. Agricultural Water Management. 187:154-163.