Agronomy and Crop Sciences Commons^™

Dynamics Of Soybean Seed Protein And Oil Content With Depth In The Canopy, Hafith Furqoni

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Understanding the physiological basis of variation in seed composition is critical for optimizing soybean seed composition. Also, studying dry matter accumulation and nitrogen uptake, partitioning, and redistribution in soybeans is crucial due to its direct impact on seed yield levels and overall plant productivity. This study aimed to test the primary proxy influencing seed protein and oil content, which is their accumulation rate determined by the assimilate supply per seed. The second objective was to comprehensively understand soybean dry matter (DM) accumulation and nitrogen (N) uptake, partitioning, and removal patterns within the canopy. Field experiments were conducted using two soybean …

Integration Of Matlab And Machine Learning To Accelerate Evaluation Of Biological Activity In Agricultural Soils And Promote Soil Health Improvement Goals, Andrew Stiven Ortiz Balsero

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

Traditionally, assessments of soil biological activity have been confined to laboratory settings, creating a disconnect with practical in-field methods. To bridge this gap, cotton fabric degradation has been used to illustrate soil microbial activity under different management practices. While effective, these demonstrations are subjective and labor-intensive.

Researchers have explored using image processing software like ImageJ and Adobe Photoshop to streamline this process. Although these tools accurately quantified fabric degradation under varying soil conditions, the methods remained labor-intensive and complex. Consequently, these methods were still not ideal for on-farm use by agricultural practitioners.

To further address labor and complexity limitations, the …

The Effects Of Cover Crop Adoption On Yield Distributions Under Extreme Drought, Emory Johnson

Graduate Theses and Dissertations

Increased frequency and severity of extreme weather events due to climate change negatively impact agriculture output. Of particular concern is the adverse impact of droughts on corn and soybean yields, as these crops represent a significant portion of cash crop receipts in the United States. Cover crops are one practice that has gained attention due to their agronomic benefits and their potential to reduce downside production risk for producers. This study focuses on the impact of cover crop adoption on corn and soybean yields during drought conditions. We use cover crop adoption data from the Operational Tillage Information System, RMA …

Agronomic Practices To Enhance Weed Management, Department Of Primary Industries And Regional Development, Western Australia

Grains and other field crops factsheets

Some agronomic practices, such as crop choice and sequence and improving crop competition and pasture competition, can improve crop environment and growth, and the crop's ability to compete with weeds.

Enhancing Crop Resilience: Physiological And Omics Approaches For Drought And Heat Stress Tolerance In Soybean And Peanut, Jyoti Prasad Kakati

All Dissertations

Soybean and peanut are two major crops globally grown for oil and protein. Climate change-associated factors like drought and increased temperature (heat stress) challenge the global production of soybeans and peanuts. Though the United States is the second-largest producer of soybean and the fourth-largest producer of peanuts, it still faces production constraints associated with drought and heat stresses. In the present study, we have examined the responses of soybean and peanut plants to drought and heat stresses during germination and reproductive phases. We conducted field and controlled environmental studies to elucidate the impact of drought stress on germination and seedling …

Use Of Herbicides Coated Onto Fertilizer And Applied Over-The-Top Of Cotton, Summer Linn

Graduate Theses and Dissertations

Cotton (Gossypium hirsutum L.) production faces numerous challenges, many related to weed management. A herbicide application method that focuses on combing resources that producers already have access to, such as herbicide-coated fertilizers, could be a practical approach for addressing late-season control of Palmer amaranth (Amaranthus palmeri S. Wats) and other problematic weed species. Two main factors would potentially impact the efficiency of utilizing this method: cotton tolerance to the application and weed control provided by the herbicide-coated fertilizers. Some considerations could affect the efficacy of these applications, such as when the treatments are applied and when they are activated by …

Evaluation Of A Diflufenican:Metribuzin:Flufenacet Premixture For Soybean Tolerance And Weed Control, Matthew Coleman Woolard

Graduate Theses and Dissertations

Palmer amaranth [Amaranthus palmeri (S.) Wats.] and waterhemp [Amaranthus tuberculatus (Moq.) Sauer] ranks among the most troublesome weeds of soybean [Glycine max (L.) Merr.], having evolved resistance to multiple herbicide sites of action. Bayer CropScience has announced its intentions to launch Convintro™ brand herbicides, one being a three-way premixture for use preplant until 3 d after planting in soybean. The premixture will include diflufenican (WSSA Group 12), metribuzin (WSSA Group 5), and flufenacet (WSSA Group 15) (DFF-containing premixture), adding a new site of action for use in soybean throughout the United States. In 2022 and 2023, field trials were conducted …

Approaches To Controlling Palmer Amaranth And Its Interference In Furrow-Irrigated Rice, Tanner Austin King

Graduate Theses and Dissertations

Palmer amaranth (Amaranthus palmeri S. Wats) is the most troublesome and problematic weed in most mid-southern U.S. row crop production systems. With the increased adoption of furrow-irrigated rice (Oryza sativa L.), there is a greater occurrence of Palmer amaranth due to sustained moist conditions allowing continual emergence of the weed throughout the growing season. Palmer amaranth has previously been shown to negatively affect crop yields when left unmanaged. Therefore, there is a high potential for rice yield loss due to the weed’s ability to emerge over an extended period and interfere with crop development. However, there is a lack of …

Evaluation Of A Capsule Suspension Formulation Of S-Metolachlor For Use In Fenclorim-Treated Rice And Wheat, Samuel Charles Noe

Graduate Theses and Dissertations

The continued evolution of herbicide resistance is one of the primary concerns facing Arkansas growers today. Problematic weeds such as barnyardgrass [Echinochloa crus-galli (L.) Beauv.] and Italian ryegrass [Lolium perenne L. ssp. multiflorum (Lam.) Husnot] have evolved resistance to some of the most used herbicides in rice (Oryza sativa L.) and wheat (Triticum aestivum L.). To counteract this resistance, alternative herbicide sites of action should be explored. S-metolachlor is a very-long-chain fatty acid (VLCFA)-inhibiting herbicide [Herbicide Resistance Action Committee (HRAC)/Weed Science Society of America (WSSA) Group 15] commonly used in U.S. row crops to control grasses and small-seeded broadleaf weeds. …

Assessment Of American Tannin-Free Grain Sorghum As Feedstuff For Poultry: Nutrient Composition, Amino Acid Digestibility And Bird Performance, Santiago Sasia

All Dissertations

Given the rising cost of poultry diets, alternative ingredients like sorghum are crucial for maximizing returns without compromising product quality. Sorghum's drought tolerance and adaptability, along with its nutritional profile, make it a viable corn substitute. This dissertation examines the nutrient composition, amino acid digestibility, and performance of poultry fed with American tannin-free grain sorghum. Chapter II evaluates the impact of sorghum-based diets, with or without phytase superdosing, on broiler performance, including body weight, weight gain, feed intake, and feed conversion ratio. Results indicate that sorghum can replace corn without adverse effects on broiler performance. Chapter III explores the partial …

Using Machine Learning To Combine Genetic And Environmental Data For Maize Grain Yield Predictions Across Multi-Environment Trials, Igor K. Fernandes, Caio C. Vieira, Kaio O.G. Dias, Samuel B. Fernandes

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Complementing phenotypic traits and molecular markers with high-dimensional data such as climate and soil information is becoming a common practice in breeding programs. This study explored new ways to combine non-genetic information in genomic prediction models using machine learning. Using the multi-environment trial data from the Genomes To Fields initiative, different models to predict maize grain yield were adjusted using various inputs: genetic, environmental, or a combination of both, either in an additive (genetic-and-environmental; G+E) or a multiplicative (genotype-by-environment interaction; GEI) manner. When including environmental data, the mean prediction accuracy of machine learning genomic prediction models increased up to 7% …

B.R. Wells Arkansas Rice Research Studies 2023, J. Hardke, X. Sha, N. Bateman

Arkansas Agricultural Experiment Station Research Series

Arkansas is the leading rice producer in the United States. The state represents 49.0% of total U.S. rice production and 49.6% of the total acres planted to rice in 2023. Rice cultural practices vary across the state and across the U.S. However, these practices are also dynamic and continue to evolve in response to changing political, environmental, and economic times. This survey was initiated in 2002 to monitor and record changes in the way Arkansas rice producers approach their livelihood. The survey was conducted by polling county extension agents in each of the counties in Arkansas that produce rice. Questions …

Economics - The Neglected Dimension Of Pasture Disease R&D, N D. Macleod

IGC Proceedings (1977-2023)

Pasture utilisation underpins a significant contribution of livestock industries to Australia’s economic well-being. Pasture disease represents a direct threat to these enterprises but the economic magnitude of this threat remains largely unknown as the contribution of agricultural economics to pasture disease R&D, management and policy making has been minimal to date. Some insights to explain this apparent neglect are highlighted and a suggestion is made for a multiple disciplinary approach to R&D.

The 'Pendulum Paradigm' - Trends In Nitrogen Fertilizer Use On Temperate Grass/ Clover Pastures, R J. Eckard, F R. Mckenzie, P A. Lane

IGC Proceedings (1977-2023)

Nitrogen fertiliser responses, on perennial ryegrass (Lolium perenne) / white clover (Trifolium repens) dominant pastures, are compared between sub-tropical South Africa and temperate Australia. The data highlight the similarity in inflection point of the response curve, while emphasising the influence of high residual soil N at lower N application rates. The propensity of communities to oscillate between extremes in terms of N fertiliser use on intensive pasture, or the ‘Pendulum Paradigm’ is discussed. Particular reference is made to the dramatic increase in N fertiliser use in dairy pasture of temperate Australia and New Zealand. Emphasis is …

Linking Grassland And Range National Goals With The Grazing Lands Conservation Initiative For National Benefit, David B. Hannaway, Walter F. Wedin, Gerald W. Evers

IGC Proceedings (1977-2023)

Grassland and Range National Goals (GRNGs) were developed to identify national research and education needs for these resources, both public and private. The Grazing Lands Conservation Initiative (GLCI) developed within the NRCS to address the need for technical assistance for the management of privately held grazing lands. These activities are complimentary and, when combined, will address the national need for research, education, and technical assistance leading to better management of grassland and range resources.

The Effect Of Grazing On Etiolated Regrowth In Eight Grass Species, H A. Lardner, S.B M. Wright, R.D H. Cohen

IGC Proceedings (1977-2023)

Grazing by herbivores affects grass species both morphologically and physiologically. A grazing study was conducted on an irrigated pasture near Outlook, Saskatchewan, Canada during the summers of 1991 and 1992 to determine etiolated regrowth after grazing of reed canarygrass (Phalaris arundinacea L.), slender wheatgrass (Elymus trachycaulus (Link) Gould ex Shinners subsp. trachycaulus), intermediate wheatgrass (Thinopyrum intermedium (Host) Barkw. & D.R. Dewey subsp. intermedium), orchardgrass (Dactylis glomerata L.), meadow bromegrass (Bromus beibersteinii Roem. & Schult.), smooth bromegrass (Bromus inermis Leyss.), tall fescue (Festuca arundinacea (Schreb.) Wimm.) and timothy (Phleum pratense L.) in …

A Vison Of The Future World Food Production And Implications For The Environment And Grasslands, Per Pinstrup Andersen, Rajul Pandya Lorch

IGC Proceedings (1977-2023)

Increases in world population, projected to rise to 8 billion by 2020, and the resultant demand for food places great pressure on our agricultural and aquacultural resources. Anxiety about the future is exacerbated by decreasing grain stocks. Production increases of many commodities are projected to be between 1 and 2% per annum and will generally be higher in developing than in developed countries. Cultivatable land area will increase in some areas of the world but not in others. To cope with these challenges, yield increases will be essential and the application of existing knowledge and technologies will not suffice. Accelerated …

Canada's Forage Resources, D Mccartney, P R. Horton

IGC Proceedings (1977-2023)

Canada is the second largest country in the world and stretches 5,500 km east to west and 4,600 km north to south. About 90% of Canada is uninhabited with 90% percent of the population living within 500 km of the Canadian-American border. About 60% of Canadians live in southern Ontario and Quebec. The grazing industry is located primarily in western Canada with British Columbia, Alberta, Saskatchewan and Manitoba having 84% of the national beef herd. Ontario and Quebec have 73% of the national dairy herd. The majority of harvested forage, dehydrated alfalfa and forage seed crops are grown in western …

Opening Ceremony Address By Chairman Of The Continuing Committee, T Nolan

IGC Proceedings (1977-2023)

Chairman and Vice-Chairman of the Board ofDirectors of the XVIII International Grassland Congress, Your Honour, Lieutenant Governor of the Province of Manitoba, Minister of Agriculture of the Province of Manitoba, Distinguished guests, members of the International Rangeland Congress, members of the International Grassland Congress, ladies and gentlemen. On behalf of the Continuing Committee, I am privileged to welcome you to the XVIII International Grassland Congress. What we will witness is the culmination of about six years of preparatory work by the Canadian Organising Committee and on your behalf! sincerely congratulate them for setting the basis for most interesting scientific and …

Closing Address: A Developing Country Perspective, Walter S. Alhassan

IGC Proceedings (1977-2023)

It is an honour to present this closing address for the XVIII International Grassland Congress and I do it on behalf of colleagues in Africa, Asia and South America. The thirty themes and over 800 papers presented reflect the growing complexity of our grasslands in shaping the general well-being of people on this planet. The XVIX Congress, to be held in Brazil in 2001, will move the frontiers of knowledge concerning sustainable use of grassland resources even further.

This address is being made from the perspective of developing countries that contain the majority of tropical pastures. This region of the …