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Full-Text Articles in Physical Sciences and Mathematics

Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan Dec 2016

Annual Forage Cropping-Systems For Midwestern Ruminant Livestock Production, John Ernest Mcmillan

Open Access Dissertations

Annual forage cropping systems are a vital aspect of livestock forage production. One area where this production system can be enhanced is the integration of novel annual forages into conventional cropping systems. Two separate projects were conducted to investigate alternative forage options in annual forage production. In the first discussed research trial, two sets of crops were sown following soft red winter wheat (Triticum aestivum L.) grain harvest, at two nitrogen application rates 56 and 112 kg ha-1 . The first set of crops were C4 summer annuals seeded within two weeks of wheat grain harvest and included, brown …


Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser Dec 2016

Residual Effects Of Nitrogen Fertilization On Soil Nitrogen Pools And Corn Growth, Meghan E. Moser

Open Access Theses

Given the dynamic nature of soil nitrogen (N), inorganic N fertilization to corn (Zea mays L.) has potential to alter N pool balance by creating an accumulation or depletion of soil N. Current corn N recommendations in the common corn-soybean rotation of Indiana strive to find the best N rate that maximizes producer profit. Increasing our understanding of soil N will inform producers if they should adjust fertilizer rates for corn to influence maintenance of organic N and Carbon. Our objective was to determine residual N effects from fertilized corn in a corn-soybean rotation by measuring (1) soil N …


Learning From Data: Plant Breeding Applications Of Machine Learning, Alencar Xavier Aug 2016

Learning From Data: Plant Breeding Applications Of Machine Learning, Alencar Xavier

Open Access Dissertations

Increasingly, new sources of data are being incorporated into plant breeding pipelines. Enormous amounts of data from field phenomics and genotyping technologies places data mining and analysis into a completely different level that is challenging from practical and theoretical standpoints. Intelligent decision-making relies on our capability of extracting from data useful information that may help us to achieve our goals more efficiently. Many plant breeders, agronomists and geneticists perform analyses without knowing relevant underlying assumptions, strengths or pitfalls of the employed methods. The study endeavors to assess statistical learning properties and plant breeding applications of supervised and unsupervised machine learning …


Liquid Swine Manure Application Timing And Instincttm Impacts On Net Soil Nitrogen Mineralization And Corn Yield, Min Xu Oct 2014

Liquid Swine Manure Application Timing And Instincttm Impacts On Net Soil Nitrogen Mineralization And Corn Yield, Min Xu

Open Access Theses

Nitrogen (N) is one of the most expensive variable input costs for corn production. Optimized manure management is essential to ensure maximum crop N utilization and to reduce the risk of N loss. A field study was conducted in central Indiana from 2011-2013 to assess liquid swine ( Sus scrofa L.) manure N availability when applied at different times or co-applied with InstinctTM , a microencapsulated form of nitrapyrin. Soil inorganic N contents, soil N mineralization, corn yield, grain N content, whole plant N concentrations of corn at the V6 growth stage, and ear leaf N concentrations of corn at …


Assessing Positional Accuracy And Correcting Point Data For Digital Soil Mapping At Varying Scales, Minerva J. Dorantes Oct 2014

Assessing Positional Accuracy And Correcting Point Data For Digital Soil Mapping At Varying Scales, Minerva J. Dorantes

Open Access Theses

Accuracy, timeliness, and the effect of scale of soil maps are rarely assessed. The recent increase in the use of GIS technologies and modelling software in natural resources and land management, has increased the demand for soil information at a finer resolution worldwide. Most of the world's developing countries rely on soils information at a scale that is too coarse for practical planning, and have obstacles impeding collection of new data, such as civil war and a lack of collection resources. The United States has an exhaustive collection of soils data at a fine scale. However, its location information is …


Observation-Based Algorithm Development For Subsurface Hydrology In Northern Temperate Wetlands, Chun-Mei Chiu Oct 2013

Observation-Based Algorithm Development For Subsurface Hydrology In Northern Temperate Wetlands, Chun-Mei Chiu

Open Access Dissertations

This study investigates wetland subsurface hydrology, as well as biogeochemistry - which is strongly influenced by water and temperature dynamics - as these interactions are expected to be highly significant, yet remain poorly represented in current ecosystem and climate models.

Northern wetlands have received widespread public attention due to steadily increasing summer mean global temperatures, extreme precipitation events and higher rates of natural greenhouse gas emissions, as well as the significant impacts on them due to human activities. The goal of my graduate research has been to improve quantification of the role of subsurface hydrology in northern wetlands by using …


Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr Jan 2013

Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr

Open Access Dissertations

The shift to concentrated animal production facilities and increasing rural-urban migration has increased the localized land application of nearly 1 billion tons of manure and biosolids annually. Although these applications provide nutrients and contribute to soil tilth, they also serve as a source for an estimated 49 tons of the natural manure-borne estrogens, 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), and estrone (E1). While these estrogens are critical to endocrine systems, the low concentrations observed in the environment can disrupt endocrine function in non-target organisms, e.g., altering secondary sex characteristics which can lead to changes in wildlife communities.

Research presented here focuses on …


Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla Jan 2013

Developing White Ash With Resistance To The Emerald Ash Borer, Kaitlin Joy Palla

Open Access Theses

Hypocotyls isolated from mature embryos germinated on Murashige and Skoog (MS) medium supplemented with 22.2 µM 6-benzyladenine (BA) and 0.5 µM thidiazuron (TDZ) were transformed using Agrobacterium tumefaciens strain EHA105 harboring the pBI121-8D2 vector containing the neomycin phosphotransferase (nptII) gene and a full length, codon-optimized Bacillus thuringiensis Cry8Da protoxin gene (cry8D2). Explants were transformed in a bacterial suspension with 100 µM acetosyringone using 90 s sonication and 10 min vacuum-infiltration. Four independent lines of transformed shoots were selectively regenerated on MS medium with 22.2 µM BA, 0.5 µM TDZ, 50 mg L-1 adenine sulfate, 10% …