Life Sciences Commons^™

Nitrogen Transfer From Cover Crops To The Subsequent Grain Crop And The Influence Of Variability In Winter Conditions, Spencer Heuchan

Electronic Thesis and Dissertation Repository

Cover crops, which are used to provide ground cover after the harvest of the grain crop, can potentially improve the sustainability of agroecosystems by reducing nutrient losses. However, few data are available to document the extent to which cover crops improve both the retention of soil nitrogen (N) and the transfer of this N to the grain crop. The efficiency of this N transfer may be further influenced by variation in winter soil temperature; for example, reduced snow cover can increase the frequency and intensity of soil freezing, which can affect the survival of cover crops and the timing of …

An Evaluation On The Effects Of Additions And Deletions Of Specific Nutrient Management Strategies On Corn Yield At Different Plant Densities, James D. Dew

Theses and Dissertations

Improved management strategies are needed to increase yield production and quality. The study aimed to determine suitable cultural practices for improved corn production. Experiments were set up at Verona and Stoneville, Mississippi, from 2020 to 2022. Treatments included row configurations (single and twin-row), plant populations (79,000 and 99,000 seeds ha-1), and six combinations of nutrients with or without fungicide. The nutrients evaluated were two nitrogen rates 235 and 314 kg N ha-1, phosphorus 45 kg P ha-1, potassium 112 kg K ha-1, sulfur 22 kg S ha-1, and zinc 11 kg Zn ha-1, and fungicide at 272 ml ha-1. In …

The Effect Of Plant Elicitor Peptide On Nematode Infected Soybean, Siyang Liu

Graduate Theses and Dissertations

Soybean (Glycine max), an important economic crop native to East Asia, is grown worldwide for its edible beans. Soybean plants are vulnerable to a wide range of diseases, and nematodes are among the worst pests of soybean. The southern root-knot nematode (Meloidogyne incognita) and soybean cyst nematode (Heterodera glycines) are both notable nematode pests of soybean, with the soybean cyst nematode causing more than 30% of total yield loss in the US. Numerous attempts have been made to control soybean nematodes over the past several decades, and genetic engineering technology has received a lot of attention in recent years. Plant …

Assessing Impacts Of Winter-Hay Feeding On Soil And Forage Nutrient Dynamics In A Rotationally-Grazed Pasture System In Arkansas, Lawrence Gordon Berry Iv

Graduate Theses and Dissertations

More than 38 % of United States’ rural land area was used for grazing (i.e., pastureland or rangeland) ruminant animals in 2017, constituting the largest private land use group. The expansive nature of these lands means that grazing and pasture management decisions have potential to impact water quality as well as profit margins. As a result, beef producers are under increased pressure from economic and environmental standpoints to limit application of nutrients beyond those required to grow the forage needed for animal consumption. At the same time, a large amount of nutrients is recycled back to pasture systems directly from …

Long-Term Changes In Soil Surface Properties As Affected By Management Practices In A Wheat-Soybean, Double-Crop System, Machaela Morrison

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Long-term agricultural sustainability and productivity are controlled by the integrative effects of different management practices on the soil. Many Arkansas producers use the double-crop system to grow soybeans [Glycine max (L.) Merr] and wheat (Triticum aestivum L.). Studying combinations of different, non-traditional, alternative agricultural techniques may help producers better understand the long-term implications of various management practice options on sustainability and productivity. The objective of this study was to evaluate the effects of agricultural management practices, including residue level, tillage, irrigation, and burning, and soil depth on the change in various soil properties from 2010 to 2020 in …

Implementación De 1.300 M2 De Arveja (Pisum Sativum L), Como Alternativa Productiva Para El Municipio De Guavatá Santander, Sergio Sáenz Sicacha

Ingeniería Agronómica

La mayoría de la población colombiana se clasifica como pobres extremos, los cuales dependen de la agricultura y de las actividades conexas como parte significativa de sus ingresos (FAO, 2012). Con el proyecto productivo de arveja (Pisum Sativum), desde el campo agrónomico se buscó fortalecer los pequeños y medianos productores por medio de intercambio de conocimientos, lo que permitió mejorar el manejo de los cultivos de interés a través de la metodología "Aprender haciendo y enseñar demostrando" donde se desarrolló un aprendizaje teórico-práctico. Del mismo modo se buscó conocer alternativas de producción a través del establecimiento del proyecto productivo del …

Soil Properties That Influence The Occurrence Of Hydrogen Sulfide Toxicity In Rice Fields, Julia Marie Fryer

Graduate Theses and Dissertations

Rice (Oryza sativa L.) producers face many challenges throughout each growing season. Hydrogen sulfide (H2S) toxicity is a physiological disorder where sulfate (SO42-) is excessively reduced to the toxic gas, H2S. This can reduce yield and, in severe cases, result in crop death. The main research objectives were to: i) understand chemical and physical characteristics in soils prone to H2S toxicity, ii) determine influential soil characteristics on the incidence of H2S toxicity, iii) determine ammonium sulfate ((NH4)2SO4) fertilizer additions influence on H2S toxicity, and iv) predict when and where H2S will occur. Three greenhouse experiments were conducted using Arkansas field …

Testing The Potential Of Novel Grain Crop Cultivation In Rural Malawi During The Dry Season Through Irrigation And Soil Modification, Jessica Truman

Undergraduate Honors Theses

This research project studied the germination and growth rates of oat and quinoa crops in Mtalimanja, Malawi. This project was part of a larger effort by General Mills and Brigham Young University researchers to increase the diversity and nutrient content of crops in impoverished countries worldwide. It was conducted from May to August 2017 during Malawi’s dry season. Tetraploid oats and quinoa, both modified to increase the protein content of harvested grains, were planted under three different soil conditions: unamended soil, soil mixed with composted chicken litter, and soil with surface-applied granular fertilizer. The research plots were watered daily except …

Nutrient Loading Reduction In A Tile Drained Agricultural Watershed Through Watershed-Scale Cover Cropping: A High Resolution Analysis, Benjamin Gerald Bruening

Theses and Dissertations

Nutrient pollution originating from agricultural regions in the Midwest is a serious issue, leading to pollution of drinking water sources as well as large hypoxic zones in the Gulf of Mexico. The source of much of this contamination has been shown to be runoff from agricultural fields in the Upper Mississippi River Basin. One method that has been shown to reduce this pollution from the Upper Mississippi River Basin is the planting of winter cover crops. Winter cover crops such as rye and tillage radish have been shown to significantly reduce nitrate exported from agricultural fields, even in tile-drained watersheds …

Soil Salinity Study In Northern Great Plains Sodium Affected Soil, Tulsi P. Kharel

Electronic Theses and Dissertations

Climate and land-use changes when combined with the marine sediments that underlay portions of the Northern Great Plains have increased the salinization and sodification risks. The objectives of this dissertation were to compare three chemical amendments (calcium chloride, sulfuric acid and gypsum) remediation strategies on water permeability and sodium (Na) transport in undisturbed soil columns and to develop a remote sensing technique to characterize salinization in South Dakota soils. Fortyeight undisturbed soil columns (30 cm x 15 cm) collected from White Lake, Redfield, and Pierpont were used to assess the chemical remediation strategies. In this study the experimental design was …

Palatability Of Teff Grass By Horses, Rachel R. Cummins

Animal Science Undergraduate Honors Theses

Most forages commonly used to feed horses have potential detriments including blister beetles or excessive fiber concentrations. Teff grass (T), a warm-season annual forage, has the potential to be a good alternative for horses because of its lack of observed disorders. Our objective was to compare preference by horses for T harvested under different conditions with that of bermudagrass (B) harvested at two maturities. Six different forages were evaluated: T harvested at the late vegetative stage (TLV), at late bloom but that incurred 33 mm of rainfall between mowing and baling (TLBR), with caryopsis visible (TES), or at soft dough …

The Influence Of Collective Action And Policy In The Development Of Local Food Systems, Lori Porreca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The modern global agrifood system has had significant negative impacts on consumers and producers. This has precipitated the rise of local food systems that are purported to improve the health and livelihoods of consumers and producers. High expectations have led to significant public and private resources dedicated to the development of local food systems. Despite this, there has been little systematic research exploring the social and institutional conditions that facilitate or frustrate local food system development.

Using a comparative case study approach, this study explored the ways local structural conditions, collective action, food system policies, and the political context affect …

Evapotranspiration Of Kentucky Bluegrass, Lynda L. Fenton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rapid population growth in arid regions of the western US is placing increased demand on water resources. Variability in precipitation and common occurrence of drought have promoted scrutiny of water use in urban lawns and gardens. However, few reliable measurements of water use of these landscapes exist. Quantifying the amount of water used vs. required by landscapes such as turfgrass would allow significant water conservation. Evapotranspiration (ET) is affected by biophysical factors such as: available energy, turbulent mixing, saturation deficit, soil water, and stomatal conductance. In order to simulate the water use by turfgrass, the relative importance of these processes …

Origins Of The Y Genome In Elymus, Pungu Okito

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Triticeae tribe DUMORTER in the grass family (Poaceae) includes the most important cereal crops such as wheat, barley, and rye. They are also economically important forage grasses. Elymus is the largest and most complex genus with approximately 150 species occurring worldwide. Asia is an important centre for the origin and diversity of perennial species in the Triticeae tribe, and more than half of the Elymus are known to occur in the Asia. Cytologically, Elymus species have a genomic formula of StH, StP, StY, StStY, StHY, StPY, and StWY. About 40% of Elymus …

Re-Integrating Crops And Livestock In Maine: An Economic Analysis Of The Potential For And Profitability Of Integrated Agricultural Production, Aaron K. Hoshide

Electronic Theses and Dissertations

This thesis examines the profitability of and sustainability indicators for potato and dairy farms in Maine integrating crops and livestock in two different ways. The first is inter-farm coupling, where two or more specialized producers are close enough to exchange manure applications for crops used as livestock feed. Land base is shared between farmers. The second is where farms are on-farm integrated. Here crops and livestock are raised on the same farm and manure is applied to cash crops and livestock feed crops. Face-to-face interviews with Maine producers were used to construct integrated and non-integrated representative budgets. Assuming …